I have used my ultralite pad long term as well as a crazy nice thermal rest dreamer pad. The ultralite got torn easily and was loud. The dreamer was better than some spring mattresses I've used.
My first winter camping trip is one I’ll never forget, my back was killing me after trying to sleep on a foam pad. The next trip, I brought a Therm-a-Rest Self-Inflating Pad and it literally changed everything. Suddenly, I was sleeping warm and supported, ready for morning hikes. I’d recommend [air mattresses](https://www.reddit.com/r/KeepThisInMind/comments/1ltzxk1/recommend_the_air_mattress_best_for_camping/) for camping to anyone, from lightweight backpacking pads to thick car-camping mats, especially for winter trips.
I know that I have two just like this, but I’ve always inflated them by mouth. Maybe I’ve doing it wrong for 25+ years, but either way these are great thermal insulation for camping.
Before you commit to cutting a pad you may want to consider the pad thickness, how the resulting drop in height might affect your sleeping position and how you could compensate for it in practice.
The Nemo Tensor All-Season specs list it at \~9cm, which you'll of course sink into some depending on inflation level, but it may be high-enough where you would need something more besides your empty backpack to rise the legs to similar level.
The Therm-A-Rest self-inflating one would have probably had 3.8cm height according to the specs. Guessing based on the specs of the currently available self-inflating ones.
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MegaMat Series
92% positive of 454 users
Car camping comfort champ, but some side sleepers find it thin.
chalhobgob
