toss up between Clevite 77's and King, but now King may be the better bearing for a 4340 assy since clevite no longer makes the wider bearing with a chamfer, instead they now just make a narrowed bearing atleast for the sm/blk chevy. I know it's not much but still less bearing surface on the rods, because the bearings are amberdextrous making them narrower on the inside side of the rod. On the cast steel and cast iron cranks the bearings are still wide and ofcourse a difference surface coating.
JMO
Zip.