Just had the at 2525 installed yesterday and I've gotta say it's the best muffler I've had. I had a flowmaster 40 and a 14 inch magnaflow oval muffler on my first gen (4 cyl) and I've had a 13 inch wicked flow max, wicked flow kamikaze, and magnapack on my 4.0l in that order, and this is the best. Idle sounds the best far and away, and although it's not quite as loud as the maganpack or kamikaze (prob get louder after broken in), it has absolutely no drone which those two had plenty of, especially in low rpms
The aero turbine sound is the deepest one yet and very smooth with no hissing or "chatter" which I feel the magnapack and kamikaze had. Ive also noticed a slight power increase with the aero compared to the magnapack, and consequently saw a gain when I changed from the kamikaze to the magnapack. So more or less the kamikaze made me lose power and mpg that was clearly visible after switching from the standard wicked flow max muffler due to the kamikaze's extreme openness. Furthermore the wicked flow max did net me an extra mpg compared to the magnapack but with the same performance, just a very mellow and boring sound. Obviously the mileage gains or loses of the aero turbine can't be determined yet, but the ears and butt dyno approve.
I'd rank them like this in overall regards to sound, performance, and mpg.
1. Aero 2525
2. 14x4 magnapack
3. Wicked flow max
4. Wicked flow kamikaze