I have ARH for about 6 years now,still woroking great
FYI ARH is a just a bunch of ex Kooks employees that went out on thier own
both are great headers
best thing you can add to your rear set up are those poly bushings
I opted for another brand on the subframe kit which I thought was better and did not need an alignment after because it was self centering
NVH,hard to tell my car has headers and so much other stuff
im assuming you are not using a whipple tune ?
I wanted to do the swap myself but CircleD said the canned tune would not work
and that seems to go in line with what im hearing . My regret is not getting a manual lol