Which one would be better for a non-turbo GS? With the EVO Ive heard you loose low end power, is that true?

yes this is true. it is because the piping is a bit bigger than the SP, from what i remember. for NA, the SP would be a better exhaust. but the differences are not that big, so most people just go for what look they like better.

Just some SP input here.....I just bought Kory's SP off of him and I didn't notice any difference from the STOCK one performance wise. All i know is that its loud as f*ck and I was wondering if i could shut it up just a bit...heh heh

I've got the SP, when I put it on I noticed quite a bit of a difference, although I also had a header and intake installed at the same time. imo, I like the way the SP sounds better than the EVO, the SP is a lot deeper and more throaty, where the evo almost has more of a honda-ish tone to it. Powerwise they're probably pretty close interms of what kind of gains you'll get, so if I were you I'd just go with what you think looks/sounds best.

yeh, i like the sp. awesome sound. no raspy dirtbike sounds there. kindof...i bottomed out a few times and i think i bent a heatshield somewhere and it's scratching at about 3krpms. i just have to get off my lazy ass and bend it back.

instead of spending all that money on just a cat back why don't you goto an exhaust shop and get a custom cat back put on with a muffler for like 3 - 4 hundred than spend the change on another mod like UDP

if you want some good muff names i'd go with

hayame
aerospeed
obx
ractive
maybe magnaflow. i have one of these now and i'm not that happy with it. not as deep as i'd like (3" tip) and it's packed really tight so it has that buzzy noise at certain revs. i sound like a cross between a SOHC civic and a high pitched harley. gross but i think it's working its way out gonna tlak to the muff guy and see about a different muff.