got the prochamber, been on since i got my gt (2 yrs now). this is my overview of it.
pita to install. (but they pretty much all are, not really mac's fault)
fitment is questionable at best, but it will go on there. (def. mac's fault)
will prob. rust quicker than some others, mine has it, just at the welds.
no leaky./ no probs. once u get it on, u can forget about it.
really wakes up the car. was my first mod. & fav. one, besides gears.
sounds bad@ass. haven't heard dr. gas, but this is best mid-pipe i've heard.
just my 2 pennies.