I don't really feel comfortable on anything less than a 3" foam rubber mattress. None the less, I favor the lighter self inflating pads for sleeping on the ground. I have a Trail Scout and a Prolite+ short pad. I usually put a 25" X 48" piece of insulating Poluethylene foam under the pad. The foam is a Z-fold that pads the back of my pack. It's not comfortable by itself, but it adds some warmth underneath. I find that the self inflating pads don't. I normally have to blow them up some to get comfortable. The Prolite+ is acceptably comfortable, the Trail Scout is marginally comfortable. I haven't had much trouble rolling or sliding off them, unless I overinflate. I try not to sleep on my side because it puts too much pressure on my shoulder. My nights on the ground are usually fitful, but I feel OK the next day.