You are talking about dynomax bullits right? If so, like most straight through mufflers, it will pretty much sound the same as SLP, the Packs, and Borla Stingers. Try searching for clips of any of those exhausts and you will find something that sounds similar.
They probaly wouldn't sound too good on a mostly stock car but if you had a big windsor with lots of compression, they sound great. Also on a stock car, it would probaly hurt lowend torque because of lack of back pressure.
Bullitts are nothing like glasspacks. Look in side a glasspack and even their 3" in/out muffler are only like 2" inside the muffler itself. Bullitts are whatever size you have in/out is what size it is inside.