i have the Greddy EVO and i like how it sounds....most people tell me how they like that it doesn't sound like a fart can like other rice exhausts.
I know someone who had the SP and that thing was a lot louder than my EVO. When I was rolling on stock rims and H &R race/Tokico Illuminas...i would scrape it every now and then...but now, with my 18's i don't scrape the exhaust at all