Dynamat. How much is enough?

I know the vehicle is off topic..... my apologies, but I did Dynamat Extreme in my Toyota Tundra a few months back while doing my new audio system. After the Dynamat was laid, I used a product called Ensolite acoustical foam to further block noise. The process was tedious and took a few weekends to complete but it was worth every penny and hour I put into it. The difference was night and day and my radio volume was literally cut in half. The truck feels like a rolling sound booth. I did 2 layers on the floors and back wall, and 2 layers on all the doors, one on the outer skin and one on the inner behind the panels.

I found my Dynamat Extreme bulk packs on ebay for $90, and I used 3 of them. For Ensolite, I bought 6 yards.

I have used RAAMat from RAAMaudio before and I have to say its in close competition to Dynamat. Very similar in quality and much cheaper in price.

http://www.raamaudio.com/cgi-bin/index.cgi