Hi,
I don't know if this is made by the same company, as mentioned in Stu's post, but I just recently replaced my worn, tired and sagging soundproofing with DYNAMAT peel and stick. It took a little cut-n-fit to get most of the areas covered and the metallic tape worked very well on the seams. There is a marked difference in engine noise. So, as far as I am concerned, it is worth the effort and cost.
Happy Sailing