im in the same boat, im trying to figure out a set of headers, exhaust and cia to get at the same time... thanks to kyle i now know the difference between the headers, but if i do the exhaust and headers will it trip my O2 sensor thus voiding any warranty? and i want some loud and a deep growl, but i cannot seem to find anything which matches what I am looking for. I have heard alot about magnaflow compared to borla, but slp and corsa seems to be popular as well.