well, the WS is quiet, no doubt about that but it depends on you how quiet you want it, and as far as i remember there's a noticeable difference between the stock exhaust and the WS..
now about my EVO..
i really like the deepness of it, its not high-pitch like the N1 and it isn't annoyin' during highway cruises... i recently drove my car with the evo on I-94 and i went 90 mph and the exhaust is hardly noticeable all i could hear was the lovely sound of it...and the music wasn't blarin' either
regular driving the evo purrs a slightly noticeable noise but once you get on it , it gets nice and aggressive!