I got the XL-
This pad is very nice to sleep on. It's too big and heavy for backpacking if you care about weight at all, but I have a smaller pad for that. In recent years I have been carrying a cot to sleep on because it's so much more comfy than the ground. That's really big and heavy. This is a nice middle ground between my lightweight Thermarest and the cot, and it fits in the tent better. The only reason for four stars is because the edges are flat welded like a thin pad typically is. Since this pad is 3" thick it would be more comfy if the edges were "square" like a mattress. I'm sure this helps it roll up better and makes it more durable, so it's a trade-off.
I do recommend getting a pump for this if you want it to be firm.
This review was written in the old system and had content requirements that are different than reviews written today.