If you’re sick of digging mud out of your underpants, a onesie offers the ultimate in all-weather protection. We have been testing two of the best, the Endura MT500 One-piece and the Dirtlej Dirtsuit Core Edition to find out which is to be crowned king.

The two best onesies on the market, the super technical, but super expensive Endura MT500 One-Piece Vs the peoples champion Dirtlej Dirtsuit Core Edition.

For many years the onesie was the ultimate fashion faux pas. 1990’s neon ski-suits were brought out of retirement only for fancy-dress shenanigans and the sight of a onesie in the ski lift queue was an open invitation for merciless heckling. But things have changed, the onesie is back – and they flipping rock! Even though we now have awesome waterproof jackets and trousers to shred in, mud and spray will inevitably find its way between the cracks, and into your underwear. When Dirtlej dropped their Classic suit back in 2016, we all laughed, then we ate humble pie as we realised it was pure brilliance.

When the weather spits it’s dummy, the best place to be is in a onesie, and the Endura MT500 One-Piece is the most technical on the market

A one-piece suit has one clear benefit, with no join between the trousers and jacket, protected like Fort Knox there is nowhere for muck and spray to get in. Even on the crappiest weather days, you know when the rain seems intent on jet-washing your face off, if you jump into a onesie you can flip the bird to mother nature while shredding to your heart’s content, warm and dry inside. For bike-parks, shuttle-days or a Scottish summer onesies are a revelation.

When in a onesie, you can flip the middle finger to wet trails, you actually start to look for puddles to detonate.

However, there are negatives to running a one-piece suit. If you’re the sort of rider who regularly ‘sends it’ into the foliage, wearing a one-piece will double the chances of ruining your day if you rip the jacket or trousers, so they need to be tough. Breathability is key too, if the sun comes out, due to the bigger pack size, you will likely have to stay in the onesie so it needs to have a lot of vents to stop you literally boiling in the bag like Uncle Ben’s rice.

Let battle commence!

We have been putting the two best onesies to the test in the world’s most rigorous outdoor waterproof testing laboratory, Scotland. If you’re in the market for the ultimate in rain protection, there are only two serious models on the market. The € 319 CORE Edition from onesie experts Dirtlej or the € 459 MT500 One-piece from Scottish based Endura.

Dirtlej CORE Edition

Samuel Jackson famously said, “AK-47, the very best there is. When you absolutely, positively got to kill every motherf**cker in the room, accept no substitutes.” When it comes to riding in the worst conditions that Mother Nature can throw at you, you need the outer shell equivalent of an AK47; tough, rugged and dependable.

The Dirtlej Dirtsuit Core Edition is packed with features, encased in a rugged durable outer.

The new Dirtlej Dirtsuit Core Edition fits that bill. Designed specifically to keep enduro and trail riders warm and dry in everything up to a full nuclear Winter; the Core Edition slots into the Dirtlej’s range as offering more protection than the Pro model and more breathability than the SFD downhill suit. We found the waterproof membrane more than capable of handling really wet conditions and the breathability is okay, if it’s not plastered in mud. 6 perforated mesh vents with waterproof zips, two on each leg and two on the chest plus two huge under-arm vents, help you regulate your temperature without letting too much nature back inside the suit. The lower legs are removable but once we got used to wearing trousers, we never bothered removing them: if the conditions require a Dirtlej, they probably require trousers. We liked that the water didn’t just run down your leg, into your shoes and it keeps all the mud off your legs and out of the shower.

The lower legs can be zipped off, but we never did. Long waterproof zips also make removing the suit over shoes easy
The CORE suit features many side vents that can be cracked open to improve ventilation
The hood has ample room to throw over a helmet while waiting in the lift queue
Waterproof stretch panels help the fit and shoulder vents shift perspiration vapour out of the suit.

The Dirtlej Dirtsuit Core Edition has a tough face fabric that feels like it would take a beating; there is a downside and this is a less supple feel than other fabrics but once riding it wasn’t really an issue. The fit and the waterproof stretch panels in the lumbar region mean that once you’re riding you soon forget that you are in a full suit and the more horrible the conditions, the quicker you forget. Overall, the fit of the large we tested is long and cut for a slim to athletic body shape: the legs are fairly baggy for easy movement and fitting armour underneath but use zips to taper the cut for riding so they don’t flap. The upper body is a bit more fitted, two velcro tabs at the waist help to keep the suit in place and give the Dirtlej some shape. The helmet sized hood is a must for waiting in uplift ques or sheltering on stops and straps down when not needed so it doesn’t act like a parachute and slow you down or fill with rain. Snug and smug in your waterproof outfit you may be but don’t forget that, once off the bike, you look like a Ghostbuster at a rave, so shy and retiring types may not relish the looks you get as you pop in for an après-ride coffee.

The Dirtlej Dirtsuit Core Edition is a heavyweight contender, but it has all the features you would hope for in a one piece

We would recommend the Dirtlej Dirtsuit Core Edition for Winter uplift days and playing in the woods, where the durability and warmth are more important than weight and pack size. For XC or day rides in changeable conditions, it lacks the versatility of separate jacket and shorts and once you decide to wear the Dirtlej you are in it all ride unless you are wearing at least a 25 ltr backpack.

Breathability: 13,000 g/m²/24h
Waterproof rating: 18,000 mm
Price: € 319
Weight: 1380 g (Large)
Info: dirtlej.com

Weather Protection


– Full body weather protection
– Good temperature regulation
– Durable fabrics


– Weight
– Less versatile
– Big pack size

Endura MT500 One-piece Suit

No ‘boil in the bag’ here, Endura’s ExoShell60 3-Layer fabric has a very high 64,000 breathability rating, ensuring high-performance during high-intensity mountain biking. Compared to the Dirtlej Dirtsuit Core Edition, the flyweight Endura MT500 One-piece is a breath of fresh air. However, at an eye-watering €459.00 anyone good at maths will see that the new one-piece suit comes in more expensive than buying a pair of MT500 trousers and jacket separately. Can the new MT500 One-piece be worth more than the sum of its parts?

With the Endura MT500 One-piece, from the front, nobody would know you are rocking the onsie.

For the image-conscious the MT500 One-piece kicks off this battle with a clear victory. Stylish and sharp, from the front the MT500 One-piece suit gives away no clue to its polarising onesie roots, looking like a conventional two-piece ensemble with a full elasticated trouser band. Only when you journey around the back do you see the connecting panel which ensures no mud or spray can claw its way in, like a mullet haircut it’s business at the front, party at the back. The Endura MT500 One-piece is certainly packed with features, zipped pockets, lift-pass holder, front vent pockets, heavy duty shoulder material with silicone non-slip details, zip-off lower legs (though we never used them) and huge 2 way-zipped vents under the arms. We really like that Endura has retained the independent trouser waist and jacket hem at the front, allowing you to climb with the jacket open without the suit losing its structure. The trousers are also really well cut for knee pads and the overall fit is slim and athletic.

Round the back, the jacket is bonded to the trousers for maximum protection, no mud is getting in here
Huge underarm vents ensure great airflow, the Endura MT500 One-piece is the suit of choice for riders looking for a year-round option
The vents continue onto the trousers, the Endura MT500 is a super sophisticated one-piece
A high collar and full hood complete the package

During testing, we were not gentle on the Endura MT500 One-piece, we abused it not only in terrible Scottish weather but also in unseasonably warm weather too. On hot days with the suit battened up fully, we were very impressed with the breathability of the fabric. The ExoShell60 fabric feels super light and airy, yes it heated up, but no more than a very good jacket and trouser combo and far superior to the Dirtlej. We see the MT500 being considered more an all-year solution than a winter shred suit, and you could certainly rock it during the hotter months on shuttles and bike parks. When the weather is in the “should have stayed at home and watched Netflix’ category the MT500 One-piece is exceptional. We tested this during long rides in what can only be considered as ‘biblical’ rain, mud and spray everywhere. Each time, when we got back to the vans and peeled off the suit, underneath we were clean enough to walk straight into work – if a bit smelly. Even after multiple trips through our long-suffering washing machine, the suit looks brand new with no delamination of the fully taped seams. If your main concern is maximum weather protection, your search is over – the Endura MT500 One-piece suit is it.

A one-piece will turn the crappiest days into a playground, but is less flexible than the matching trousers and jacket

Our only slight concerns with the Endura MT500 One-piece suit is that it lacks the heavy-duty, highly durable feel of the Dirtlej Dirtsuit Core Edition suit. While we know from their award-winning waterproof jacket that the MT500 range is super tough, at €459.00 we would not want to crash too much in this suit. For ‘batten down the hatches’ protection, the Endura MT500 One-piece easily matches the Dirtlej, and also adds impressive adds lightness and breathability – but at a cost.

Breathability: 64,000 g/m²/24h
Waterproof rating: 18,000 mm
Price: € 459.00
Weight: 840g (medium)
Info: endurasport.com

Weather Protection


– Total weather protection
– Great features
– Super lightweight


– More expensive than separates
– Less versatile

Conclusion: Which Onesie Is Best?

For absolute protection, both the Dirtlej Dirtsuit Core Edition and Endura MT500 One-piece both offer superb performance and we would happily ride both into battle with the elements. After intensive testing, we were left thinking that 90% of riders would be best off investing in a good jacket and separate trousers, which gives almost the same level of protection, far more versatility and saves a little money in the process too. However, if you’re the sort of nutcase who regularly leaves the house for a ride in filthy rain, or loves a wet-weather uplift; the Endura MT500 one-piece is the most high-performance and weather resistant solution on the market. However, the (relative) affordability, rugged durability and no-nonsense protection of the Dirtlej Dirtsuit Core Edition make it our top pick for filthy winter shredding!

It was a tough battle but we have a victor

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