When I ordered some FatMat for
Sound Deadener Showdown it took them about 2 months to get it to me. I called repeatedly and each time they told me it had shipped a few days before. I e-mailed a bunch of times and they never responded. They finally sent it after I told the story on another forum.
Any of the asphalt based vibration dampers are going to be chancy, especially if you live somewhere warm. They may be OK, may not. All of them, except Brown Bread, Dynamat Original and the stuff sold by Parts Express - same as Dynamat Original - are roofing repair material - MFM Peel & Seal, Protecto Wrap or something like that. I have it on good authority that FatMat is MFM Peel & Seal.
It depends on the batch, how old it is and how it has been stored before it gets to you. Like I said, the asphalt mats are iffy. Search around and you will find many people having problems and many doing OK. Search for the butyl products - Dynamat Xtreme, Second Skin, RAAMmat, B-Quiet Ultimate (not Extreme) and I have not been able to find a single reported failure.
Everything I have seen makes it clear that butyl is not only more durable than asphalt, but much more effective at damping vibration. I've also had several reports, from seemingly reliable sources, that asphalt mats produce toxic fumes in enclosed spaces.
When you compare the price difference and then consider that asphalt may or may not stick, is less effective, may or may not be toxic - well, you can see where I am gong with this
