i've got the series 2 kit. springs, shocks, and fixed lower control arms. i wasn't impressed with their adj track bar at the time, so i got a Pro Comp unit (they have a new one now that i'd run though).
i'm VERY happy with the kit. it's crazy flexy and my Jeep goes anywhere i point it. it also rides pretty much the same as it did stock. all around, it's a great kit for a CHEAP price.
cave... scroll up yourself, that's what you're all complaining about NOW in this thread, and it just simply isn't the case anymore. i personally know at least a dozen people running RC kits and there are ZERO complaints about the ride or quality. TJ, JK, XJ... all satisfied customers.