Guide me please. Sound deadener?

[jorgensensc]

Okay so I have done a search, and am still confused. I even read the very good article that one man tested all the different types of sound deadeners, but that is now dated material. So here is my question. What are you using. I think I have narrowed it down to FAt Mat Rattle trap, and Fat Mat Mega Mat, or Second Skin Dampener. I still don't completely understand the Whole BUtyl thing vs mixed asphalt/Butyl thing. This will be going in the wifes burb with dual dynomax mufflers and a 402 BB. She needs to be able to drive it and conduct business (conference calls and such) and be able to actually hear on the phone. This will eventually be her daily driver so it needs to be similar creature comfort wise to a newer vehicle. I already have A.C. etc, so now we need to get the sounds under control. Right now the carpet isn't in yet and almost have all the door seals installed, but it is an echo chamber for the exhaust and almost gives you a headache when driving around. What are you guys using? How much would I need for a suburban. I figure the whole floor, the roof (under the headliner) the door panels as well as the cargo wall areas. I know this is semi an audio question, but not completely. So moderators if you must move this please feel free to do so, but I would prefer it in this section.
Thanks all!
Shawn