ive used FatMat, Dynamat, and soon I'm getting alpha damp and some damp pro.
FatMat is just terrible all the way around.. like Jon said it smells and doesn't stick very long.
Dynamat is better than FatMat but i just want something better. I got the samples of alpha damp and damp pro Jon sent me and compared them to Dynamat. The alpha damp is WAY better quality than Dynamat, and LOL at FatMat compared to alpha damp.. damp pro and Dynamat are very similar but I feel that damp pro is going to be a little better quality.
The alpha damp is going on my roof and the damp pro is going everywhere else.