Hi. I'm no professional and fairly new to modding Evo's, but I'd say they are quite mild. Gsc s1's are 272/272 if im not mistaken, and I've just bought some s2's which are 274/274 which aren't overly aggressive as far as I know. I guess I'll find out for sure when I get the back next weekend tho. Once again, I'm no professional, but new springs are recommended on my 274's but not essential, so I'd assume the standard springs would be ok on your setup but I'm nowhere near positive. Sorry I can't give you a more straight answer but seeing as no one else has replied I thought I'd share my limited knowledge. I hope that's some help