i have the apo sironar digital 180 (not the HR), bought for cheap... stock sale from a pro shop...
didn't used much for now, but i was pleased with the result !
But i think that lens is discontinued !
I have heard good things about the schneider 210.
PS : i've also heard that nikon W lenses 150, and 180 works much better than apo-symmar equivalent for digital !
I've test an apo symmar 120 vs my apo sironar digital 90 for inf. focus... the 90 was much better... but longer is the lens, less dramatic is the difference !
By the way, congratulation for the RM3D !