Chip, I am running RPM heads that I blended slightly at home (by eye/common sense...I don't have a flow bench), and a .630 gross lift Custom Comp that was ordered from Dwayne Porter.

Off the shelf bearing selection is kind of limiting.
at least 440 source has chamfered mains available.

Old ('70s) publications used to discuss various ways builders would massage the bearings for a desired end result. I've never done anything like that myself, but it is funny how it is almost a taboo topic these days.