I reviewed Therm-a-Rest's NeoAir XLite back in lockdown 2020. With a balance of warmth and weight that's really well suited to 3-4 season backpacking, I have got on very happily with that mat over the last couple of years. But it came with one big annoyance: a loud crisp-packet rustle every time you rolled over.

Well the good news is that an update to this mat has mostly solved the issue. Not only is the NeoAir XLite NXT (next generation) a tad warmer than the original, at no increase in weight, but it is also substantially quieter. While it's not quite silent, the worst of the crinkle has now been muted, leaving me with almost nothing to criticise. Therm-a-Rest should be onto a winner here. 

Weight, pack size and durability

Previously I reviewed a wider mat, but in the interests of saving weight with summer backpacking particularly in mind I went for a Regular length and width this time. This weighs just 384g (Therm-a-Rest say 350g) with an extra 68g for the stuff sack and pump bag. You can get lighter inflatable mats and you can get warmer, more heavily insulated ones; but if you want something light enough for minimalist missions and yet with sufficient insulating oomph for at least some UK winter or summer alpine use, then the warmth for weight on offer here must be one of the best on the market. It's compact when rolled away, too, packing down to about the size of a 1-litre bottle.

With an inflatable mat there's always a slight worry about punctures, and I have holed a few in the past. As these things go, its 30D Nylon fabric feels pretty tough, and this mat doesn't give the impression it needs to be treated with quite the care you'd give some lightweights. A small repair kit comes included, and on a multi-day trip it'd be well worth bringing. If something did go wrong, it may be covered by the product's two-year warranty.

Dimensions

A rectangular version is available, but comes at a cost and weight penalty. The tapered lozenge shape of the standard model maximises the usable area while keeping a lid on weight and bulk, so this is the one I imagine will be more likely to appeal to backpackers and mountaineers.

Four sizes are available, from Regular Short (168cm long by 51cm at the wide point, £210) to the whopping Large (196 x 64cm, £250). At 183 x 51cm, Regular (also £210) is exactly the same length as I am, which just works for me - and no more - with an inflatable pillow. I'm fairly broad, and find the width just about adequate, but it's borderline. I can roll over without ending up on the ground, but when lying on my back my arms do tend to flop off the sides. For me a few more centimetres in width wouldn't go amiss, but it's bearable as-is. Regular Wide weighs about 90g more, and I've been happy so far with the weight saving/mat space tradeoff on my narrower version.

Sleeping comfort

Thickness is one of the NeoAir XLite NXT's strong points. A deeper mat smooths over uneven ground, soaking up lumps and bumps that you might feel through something thinner. At a hefty 7.6cm in depth, this is one of the chunkiest lightweight inflatable mats I've used. The difference in comfort over something skimpy is very noticeable.

I prefer vertical baffles, which somehow seem to hold you more centred on the mat, but the horizontal baffles here aren't too pronounced and ridgey. The firmness is fantastic too, giving you a nice supported feel. Experience so far suggests that even on a tricky pitch a comfortable night's sleep is pretty much guaranteed with this new NeoAir. 

Warmth 

Inside the mat, its stacked triangular baffles and heat-reflective coating help give it good insulating performance without adding much weight or bulk. For something this light it does seem pretty darn warm. While the previous version was already quite well insulated for its weight, with an R-value of 4.2, the insulation in the NXT has had a modest boost, to give you a pretty generous 4.5. This is a lot warmer than a non-insulated mat, but some way short of beefy winter models with R-values of 5, 6 or 7.

With the NXT you should often be able get away with a lighter sleeping bag, perhaps saving some weight overall. Its warmth might be more than you strictly need for UK summer use, but it makes the mat more versatile, giving you one model that will suffice across a broad range of conditions.

In serious sub-zero winter cold, or what passes for it in the UK, I would personally pack a more heavily-insulated model in preference to this mat; but in less extreme conditions the NeoAir XLite NXT has proved more than adequate. I've used it very happily on chilly spring and autumn nights, even below freezing with a heavy frost, and on the strength of that I'd consider it a 3-4 season model.

Inflation and deflation

As per the previous version, this mat features Therm-a-Rest's WingLock valve, which is claimed to be faster to inflate and deflate than the old style twist valve. With a chunky twist mechanism that's big enough to be usable wearing gloves, and a locking/unlocking 'wing' feature that's intuitive to operate, I like the design. It also gives the impression of being potentially more robust than the little rubber valves that many camping mats use these days - I've certainly had no issues with my 2020 mat as yet.

Despite the wider valve I find it takes quite some time to inflate a mat this thick, even with the pump sack provided; on the other hand deflation is really quick.

Ethics and environment

Almost all Therm-a-Rest's mats sold in the European market are made in Ireland, which means European labour and environmental standards (generally better than those in the Far East), and far fewer product miles. For me this is a massive selling point, and on both ethical and environmental grounds I do wish outdoor brands in general would manufacture more in-market, and bring the industry home.