I have abused my southbend clutch for years on a stock flywheel w/o a single problem. around 450 RWHP. It is noisy tho. The carbon side looks like new, the metallic side/flywheel side has some mild-mod wear. I have never had it slip. I just pulled the engine this wk end to do more mods. Clutch is holding up well. I would use Southbend again.