suburban dynamat vs others

[madmaxburban]

Was wondering was going to use Dynamat for floors and roof and was wondering if there was other cheaper or just as good product out there to use a buddy of mine said I could go to local hardware and use aluminum waterproof membrane that they use on houses and he used on his truck for a fraction of the cost to dynamat. Other option b-quiet is also cheaper. Please any thoughts or suggestions would be helpful. Cheers