the puck clutches will hold much more power, but will be less friendly on the street, and less forgiving to the driver. I have a spec stage III disc with an HKS pressure plate, and its grabby as hell. It has broken in some, but I remember bumpins with Spec III disc/pp was still a little prone to chatter.

If you're gonna be daily driving, and your power goals for the near future are 300 or less to the wheels for a while, a spec II is a great choice. On the other hand if auto-x, drift, and/or higher hp outputs are your goal (and non-daily driver duty), then a stage III would be fine. Honestly I couldnt see the need for more than a stage III unless you're in the 400+whp range.

Thats what Ive gathered so far, im sure matt or scott will give you a solid answer though. good luck whatever you choose.