I've hear they sound like S**T..... Flowtech is known for cheap product's as well. Stick with brand's like Flowmaster, Borla, Dynomax, Magnaflow, Spintech etc. etc. they all make decent muffler's for your Stang.
Spintech's or Dynomax Bullets(LOUD) are the only way to go..... But that's my opinion. I had Flowmaster 40's behind my 408 and I swapped them for Bullets and havn't regreted it once since. Muffler's are alway's a trial and error, you basically got to try a couple of diff. muffler's before you find the sound you want. I've been hearing so many good thing's about Spintech's that I would look into them man, sound's like there what you need. Or the Bullet's.... your choice
i had flows and warlocks on my car but it was a 3.8. liked the warlock because they didnt have the drone. if you got the one with the plug you could pull it out and run a straight pipe. it is all just a matter of opinion.
I agree with 408. As soon as I can afford to switch, I'm going to get Spintech subframe connectors and side-exit exhaust. All of the clips I've heard with that setup sound really, really nice.