I'll begin with this... I know these are Pepboy commodity mufflers, and with their low price, people scoff at the thought putting a Thrush muffler of their car. So here's the story of why there's one on mine. About three months ago, I had the itch to get some more noise out of my Corolla. I had been browsing these forums, and noticed most people either went Borla or Magnaflow. I was dead set on the Borla, I just had to figure out I could get it put on, since I don't have a welder, I called all of my local shops and got quotes. The average price for a shop to install it was around $200, but those prices were subject to change. All this means, Muffler cost+Shop Cost=$300+ dollars. No thanks, for that money I could've bought the Borla Axel Back and installed the damn thing myself. Too bad I wasn't crazy about the sound it put out. So, with that, I called my buddy and asked him for advice. He has his own welder (he does his mechanic side hustle thing, shout out to Sparky), and offered his services. I told him what muffler I was going to get, his exact words were "You don't need no dang Borla." He then told me his Kia Spectra 5 has a Thrush Turbo, and I've always liked the way his car sounded. My inner redneck penny pincher side kicked in, resulting in me buying the Thrush Muff at Autozone (I also didn't want to risk screwing up a $100 muff). With a couple adapters, beer, and an afternoon, we had it welded up.
Now that story time is over.
The exact muffler I use is the Thrush Turbo 2.25" offset/offset PN#11714. I gotta say, of course IMO, it sounds great. The sound doesn't quite rumble at idle, just kinda purrs. During normal driving, it's not obnoxious, and sometimes it sounds stock inside. Now, when you drive it like you stole it, it puts out an aggressive tone, without sounding like a fart-canned Honda. I swear the angels sang the first time I took it to redline. And I gotta say, it sounds comparable to other mufflers for a 1/3 of the price. Performance gain? Eh, maybe.. any universal muffler by itself isn't going to yield much noticeable difference. From what my butt dyno says, it maybe, just maybe, has more punch in the midrange. The concern I have with it is long term durability, being that it's a $30 muffler. Other than that, I think it was $30 well spent.
Excuse messy welds, my buddy is a good welder, not a great one.
tl:dr A Thrush Turbo muffler is a cheap and effective way to add some noise.