Exhaust Catback

Mac's or Borla's

Borla all the way for me. Totally worth the price. Also, none of the videos you watch will give you a good representation of the sound. Your best bet is to narrow it down to 2-3 sets and find people who have that setup in your area and just go check them out in person.

I have Magnaflow cat backs running out of the factory manifolds and cats. Idle is low and throaty, but not very loud. Cruise is smooth and WOT has a pretty racey, low pitched scream but isn't overbearingly loud. High quality exhaust with great tone, but don't expect to set off any car alarms. It's also a little pricey. I'll check back in a few weeks and give some feedback on how it sounds with MAC long tubes and an off road X-pipe, both before and after supercharging.

I wouldn't waste the money on a full cat-back at all. The stock pipe is 2.5" and flows plenty well, all you are gaining is the sound from the mufflers. The power gains from changing a cat-back or axle back on a 2005+ GT are minimal to none so don't spend all that extra cash on a cat back. Axle back is all you need. To make power with exhaust mods on a 3V, you need a cold air induction, longtubes and a tune. Sound wise, MAC sounds great and of course Borla and JBA sound great but are pricey. Flowmasters classic sound is for some but not others, and to me Magnaflow is just too low and mellow on a stock engine, doesn't open up throaty enough for me.