Slightly warmer and quieter... the foam on the roof is 1/2" closed-cell foam (with two layers in the middle to help get rid of the puddle that always forms there), the carpet is cheap indoor/outdoor carpet on heavy padding.
Things I learned:
1) Don't be clever!
2) Carpet is flat, and does not like being any other shape.
I cut the carpet so I could pull it out and put it back in without removing the seats... BAD IDEA. much, much more cutting, and makes it harder to get it to stay in one spot and sit flat.
--Randy