I haven't heard the KB one, but I love my Mac duals. It's got a nice low rpm tone, and as it climbs, it gets a little less throaty and more 'high pitched' (though it isn't at all high pitched compared to say a Cougar).
Hey guys, thanks for the info. So it's 2 thumbs-up for the MAC system. Their prices are pretty good so I think I'll let my nephew know that he'd be best off with that setup.
I looked at the PaceSetter website and it says that it's adapter pipe will work with 2 1/2" system that they sell or I would guess any other after market 2 1/2" system. My stock 2001 GT dual exhaust has 2 1/4" pipes I think so I doubt if it will fit.
hum i figured they had a 2 1/4 adapter, you do not want to put 2 1/2 exhaust on a v6, stick with 2 1/4 all you really need is a flange to bolt to you COULD have it welded in... but you wont be able to remove it easily to get to the tranny or driveshaft or any of that. mac offers a direct bolt in though its not true dual exhaust but its decent.
Spector, yea, I agree with you. I'm sure where there's a will there's a way. My nephew is not prepared mechanically to do the work himself so he would need to buy all the necessary parts and then have a muffler shop weld things up for him. And like you said, pulling things apart later would not be easy. Given that he'd have to take everything to a shop to get done I think that it won't be much more expensive for him just to get the MAC setup since that can be bolted together he'll be able to do it himself.