Thermarests Mira HD sleeping bag has a women's specific cut which shifts volume from the shoulders to the hips maximising loft and helping retain warmth. It has a shorter cut than a men's sleeping bag which reduces potentially cold empty space at the foot of the sleeping bag. Watch out for sizing as our 5ft 6in tester found space reduced to virtually nothing in the regular size, so it's worth checking lengths carefully on Thermarest's website before buying.
The shape works really well, allowing enough freedom of movement to feel comfortable but still staying warm throughout a cold spring night. The thermal collar is nice and thick and the drawcord adjustable hood is very effective. The sumptuous, fleecy footwarmer box inside the sleeping bag is a great touch that quickly warms your feet up and keeps them warm through the night.
The Thermacapture system, which reflects body heat back in towards you, helps to give the Mira HD a comfort rating of -3 degrees C, which is impressive for a bag that only weighs 820g. The downside to this is that it makes the sleeping bag quite rustly in use, especially if you toss and turn a lot at night. It's not a bad trade-off for a warm night's sleep but hopefully Thermarest will develop a less rustly solution soon.
Thermarest generously includes a large storage bag as well as a stuff sack with the Mira HD although we would have expected to see compression straps on the stuff sack considering how compressible the 750 fill hydrophobic down is.
The outer of the Mira HD is a highly durable 20d ripstop fabric which completes the overall impression of a top of the range sleeping bag.
Although expensive compared to some, this sleeping bag works fantastically well, is lightweight, and has a small pack size, is well made and durable so comes highly recommended for someone that values performance over all else.