We do a lot of camping and I've been a scout leader for years, taking groups to Philmont Scout Ranch, Seabase, Northern Tier and much on the Appalachian Trail.
We all reach the same conclusion over the years. The foam "egg carton" type camping pad is the best. Period. It provides great insulation, works to your body size and shape, and is durable.
I liked thermarest, but they tend to get holes in them and they are very hard to patch. They are also rather expensive. Once you've worn a hole, its a goner.
Air mattresses have the same problem. If you don't fully inflate it, for more comfort, as you shift around it makes noise - my wife called it like sleeping beside an iron lung all night.
Many different companies all make the foam egg carton pads - they're inexpensive, of different thicknesses based upon personal preferences, and are the best. From hundreds of field tests with kids and adults.
Enjoy your trip!