I belive flowmaster makes a quiter muffler that you can use with thier catback.....a 40 series I belive.

 

Cool, I've never heard a Magnaflow system, but from the way you describe it, it seems nice.

 

Ive heard great things about the Magnaflow, might be something for you to check into..

I have personal experience with...
1- SLP 2otl stock manifolds with cats (nice)
2- SLP Loudmouth stock manifolds with cats (loud)
3- 3 inch true duals, hooker LTs, x pipe, bullets, no cats (loud and i love it but have to get rid of it because of my new torque arm setup, going with 3 inch off road y pipe and Loudmouth again.. Im predicting loud)

Stay away from 2 and 3 if you are looking for quiet, those systems have great flow, but they are also too loud for most people... I liked the 2otl a lot, only reason I got rid of it is because a member here (LT1UltraZ) talked me into trading me his Loudmouth for my 2otl. If I were looking for quiet and still have good flow, I would get a 2otl again.

 

I have the dynomax ultra flow and it is very quiet, i'd say a bit louder than stock...atleast till you get on it. You do not hear the slightest bit of exhaust drone or anything inside the car. I got the one that was 3" in and dual 3" out. The muffler is pretty much straight through with packing. I have an electric cutout for when i want to be loud!

 

Go to this site and look around. You can pick different flows and loudness with these mufflers. I know several people who run them and think that they are the best...