I have Borla. Of the free flow exhausts this is probably the quietest. It is only slightly noisier on cruising speeds and pretty noisy under hard acceleration.

 

I have always put Magnaflow on my vehicles (not gotten one yet on my brand new 2015 JKU though). I had one on my 2008 JK and it sounded PERFECT! It was quiet in the cab but definitely had a little rumble to it if you were standing behind it when I started it up. The idle was loud enough to hear it had a nice muffler, but quiet enough to whisper standing behind the Jeep. If you didn't mash the gas the sound stayed nice and quiet (always with a nice deep rumble though) until you really mashed the pedal and then you got a louder roar, though it never got annoying! You won't wake anyone up with Magnaflow keeping your neighbors happy.... but when you start it up in a parking lot or pull up to a light with someone else's windows down you will get a look like (has that thing got a V8 in it?!?).

My vote is Magnaflow all the way!

 

Which system, by chance?
The axle back or the full cat-back?
One option that has a great tone but quiet at cruise is our VT cat-back system.

Good luck in your search.
Our 90 day day sound and performance guarantee

http://www.dynomax.com/warranty-guarantee/

 

I went with Banks Monster exhaust along with their CAI and could not be happier. I worried about the raspy sound and drone but have neither. Extremely quite at cruising speeds. Only get loud when you get it high in rpm range. Maybe it is the combo of both systems but I notice more pep also.

 

Although they're quite different, I'm running a Borla exhaust on my MKIV 1.8L Turbo Jetta. My aim on this vehicle was power to the wheels. Surprisingly, after testing 5 different exhausts on the dyno, it proved to produce the most low end torque, top end HP, AND it has the mellowest most throaty sound of any of the tested exhausts. Soaking the packing with water (those who know, know) gives me almost 8 more ponies and only takes less than a ft. lbs. of torque away, but makes it quite a bit louder. Given that this is on a highly modified turbo in-line four banger, I don't know how it'll go toe to toe against other exhausts on a bone stock, locked ECU V6, but this is going to be my first trial exhaust as soon as I start tuning the engine on my rig. I too like quiet, but we gotta remember that ultimately, on a Jeep, it's torque we're after. If you DO find a good power producer that keeps the rig on the hush, please share your results with us.