ive had borla on mine for about 2years now and it sounds and works great IMO. just with the catback sounded nice and resonant all the way through. with a new y pipe and gutted manifolds it is very resonant with a nice growl at WOT. i agree completely with the low end power gains and not so much up top but overall a very good exhaust system. mine doesnt show a sign of rust and the slip-joints show no leaks yet (as long as you tighten up every once in a while due to the bolt-on). hope this helps.
