mac and bbk are both pretty much the same imo, just which ever one u could get cheaper to me, if it was my choice i would go with mac just cause for some reason i dont trust bbk, u dont do that tho, its just some weird feeling ive had never had a bad eperience or anything just like the mac name better, probaly an x pipe is better, not sure really, shorties arent a bad choice long tubes are less resticting, r u getting equal? or unequal? overall u cant really make a bad choice on headers unless u get the cheapest kind then there not gonna be worth it but u get what im saying the pipe and muffler/cat back is where all the sound comes from so that would be a bigger decision then what headers to choose