[jeffast]

i have a stage 1 excedy clutch in my svx, it has all the grip i could ever need.
I reccomend going stage 1 unless you need the extra grip. it actually says on most web sites that stage 2-3 clutches are reccomended for track use only. reason being they don't last as long. also going with a quality brand name clutch usually means that it's going to last longer and grip better then some noname stage w/e brand.
also +1 on look for actual dyno # that the clutch can hold
also is your tranny hydrolic, or cable actuated?
all that really matters with subarus is wether it's a puller or a pusher, if you have a hydrolic tranniy you have a puller clutch, and the wrx clutch will work. If you have a cable trannie it's a pusher and you should be looking for a 2.5 rs clutch.
enjoy
jeff