The only problem I have with the centerforce is the weight. They are heavy. Also I've only used the dual friction and they work good, heard bad things about the "stage 1" units. The exedy's are suposed to be good, no personal experience though.
i have a centerforce 1 in my 240z, its a brand new broken in clutch and its slipping now, but i have a high comp motor. It should handle my hp but it sux so it doesnt. I have heard its basically a stock clutch with stronger springs.
My buddy has an exedy and it grips good. centerforce dual frictions are the ones to get, but they are pricey
I drove my oem exeddy clutch for about 200mi before having the engine at 2000rpm and coming off the clutch while increaseing throttle as fast as possible to keep the engine truning 2000rpm (obviously untill i got off the clutch) and the disc warped. After droping the trans again i measured the runout on the disc to be .020 ( i measured closer to the center than my factory service manual specifies) ( i believe i was 3 in away from the center when i measured the runout).
I put another oem disc in took it easy for a bit longer ~500mi ended up warping that one too. This time it only warped bad enough to cause chatter. The chatter would temporaly clear up and then come back if i launched sort of hard or was stuck in stop and go traffic.
I have to finish putting my car back together but iam trying a CenterForce stage II clutch. I almost went with the dual friction but decided i reall dont need that much clutch.
Stage II is rated for 60% more power, Dual fric is rated for 100% more power.
Iam going to be doing good if i can make 180 out of my N/A 280z