At what point would you step up to ferrea hollow stem valves

Man,....I can't recall which Member here had a set of prototype beehive triples they were about to run thru the gauntlet, @AndyF , or @IQ52 , or.......pretty sure it wasn't JRob @RAMM.....it was in the B/RB forum.....lost track of that thread....among a bunch of other stuff....lol!