I've always used the roller bearing type that is supplied with the better quality clutch assemblies. The cheaper clutch assemblies (Lok) seem to be the ones with the solid bushing type.
Besides, there are more parts!
The Old Guy! '94 z-28, m-6, t-tops, go-fast red, 316k. Now with '96 engine w/ Lt-4 hot cam, roller rockers, heavy duty timing chain, and Spec stage 2 clutch.
As a counter point, the roller bearings have been know to self-destruct. The solid bushing won't. When the roller goes, it can eventually take out the input shaft and it's bearing.
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