Before I bought my truck from my friend he put a flowmaster super 44 on it and welded a straight pipe after that. Sounds pretty darn good save for the 43123 coathangers holding it up that I have to get around fixing... His dad has a glasspack on his ZR2 S10 and it isnt nearly as loud as my flowmaster nor does it even sound good.

EDIT: Oh and when you rev it real high it pops when it tones down, it's really cool

 

it pops without a muffler as well, but yes I had a flowmaster 40 series there wasn't much of a sound difference between the tailpipe being chopped off right after the muffler and no muffler at all.

http://www.youtube.com/watch?v=QkFQAo5NzEw

 

I love that popping sound! Mine doesn't really do it though. Sometimes it does but really quiet and not noticable at all. Might have something to do with replacing the catalytic converter when I put the muffler on.

 

if you cut out your muffler and install a cherry bomb glass pack muffler (which are pretty darn cheap) and then just run a 45 degree pipe off of the muffler, its super loud. sure you wont be able to see an exhaust pipe from the back of the car anymore.. but it will be crazy loud and completely street legal

here is a cherry bomb extreme i found.. its only 55 bucks!
http://buycherrybomb.com/catalog/pro...roducts_id=139

benedict has the right idea! sounds great btw