These lifters in motors which would be called lifter eaters (big duke/chief motors) last twice as long as a comp or isky, 375 passes on one set I know of and took them out and looked perfect.
I've seen almost every brand break but the most common one's to fail are isky and comp. I know even isky were telling people they were having a problem with the oiling holes, a buddy of mine had less then 20 passes on a set that went bad.
Its a well known fact that several companys buy these "new design" lifters from Morel. My new lunati's are morels.