Therm-a-Rest's Evolite Plus combines foam and air mattress technology. Photo: Bob Smith/grough

Price: £120 (regular); £150 (large)
Weight: 710g, regular (including stuffsack)
Colour: orange
Country of manufacture: Ireland

The two things I look for in a sleep mat are comfort and insulation.

Traditional closed-foam mats provide the latter but not much of the former. Lightweight airbeds score better on comfort, but by the time you’ve blown them up in the confines of your tent while a storm lashes the hillside, your head can be spinning.

Therm-a-Rest’s Evolite mattress combines both foam and air pockets and is largely self-inflating, thanks to its AirFrame skeleton of foam interspersed with air-filled areas. Take the mattress out of its stuffsack, open its valve and, within a short time, it has reached almost its full loft. It took less than half a dozen blows then to achieve a good inflation.

The Evolite Plus has the added benefit of ThermaCapture technology – a reflective internal layer – which helps give better insulation.

All this comes in a reasonable weight of a little over 700g and packs into a small stuffsack 25cm high and 16cm diameter, so it doesn’t take up too much space in your pack.

These specs are for the regular version, which is 51cm wide and 183cm long. A more expensive and heavier large version is also available, giving an extra 12cm across its width and 13cm length.

The foot area tapers, which meant there is a tendency for the feet to wander off the mat through the night, but this was a minor irritation and overall we found the length and width of the mattress just about right, though back sleepers might find their arms hanging over the edge.

The loft of 6.4cm is enough to provide comfort for a good sleep.

The Evolite Plus

The face fabric, both top and bottom, is a fairly tough 30 denier polyester, but as with all inflatable mattresses, care should be taken not to place it on any sharp objects that could puncture it.

The R-value rating for the Evolite Plus is 3.2, thanks to its added reflective layer, and in use the mattress provided good warmth, even in temperatures close to freezing.

Packing the Evolite Plus back into its stuffsack takes some effort, as the self-inflating nature of the mattress means it keeps trying to do exactly that, even when you want to deflate it. The trick is to open the valve, fold it a few times from the foot end to get most of the air out, and close the valve.

Then fold the mat into thirds lengthways (tricky!) and roll it so any air left is squeezed up towards the valve. You then open the valve again and roll the Therm-a-Rest mattress to expel the remaining air. Close the valve and the mat should be just about small enough to get into the stuffsack. At least the task warms you up on a cool morning.

When you get back to the comfort of your home, take the mattress out of the stuffsack and hang it in its inflated state so as not to lead to long-term compression of the foam.

We liked the Therm-a-Rest Evolite Plus. It was warm enough for what might be termed three-season use, and comfortable, with a face fabric that wasn’t too slippery. The mixture of foam and air also gives the mattress a slightly flatter profile than a pure air mattress, so there’s less tendency to slide off it through the night.

Comfort: 35/40
Warmth: 22/30
Ease of use: 7/10
Quality: 8/10
Value for money: 6/10
Total score: 78/100

• The Evolite Plus was supplied to grough by Therm-a-Rest