I have two pads that I use depending on the bag I pack: the BA Insulated Q-Core, and an Exped DownMat 9. Both are great pads--warm and comfortable. The advantage to the Q-Core is pack size and weight as it is considerably smaller than the Exped.
I tend to be a "cold" sleeper and generally pack a bag that is 10 to 15 degrees warmer than than the lowest expected temps. I have used the Q-Core with a 15 degree BA Down bag down to the mid-20's and been very comfortable with only a light base layer. I am a big guy at 6'4" and 245# and the pad is very comfortable even as a side sleeper.
Once concern (as with any inflatable pad) is to make certain that the tent floor or the ground is clear of stickers or cactus as it would not take much of a "stick" to have a guy on the ground.
I would highly recommend the pad, and as always, Backcountry's customer service is second to none.