I use wool fore everything with my horse.
Another one I have has neoprene with just a fabric top. Sometimes I use that one, but on my other horse and saddle. It's just the one I have that fits that one saddle right now, though.
But wit my current horse I use like a wool saddle back. It works really nicely and it was really nice when we went on a 14 mile trial ride. I like them.