Range day today:
Shot both revolvers with the same load, a mild .357 handload of a 158gr Nosler JHP over HS-6. Both guns are super smooth and track wonderfully from target to target. Made the decision to sell the 65-5, though, as I shot the 66-2 just a hair better and I've got a few other projects I need to raise funds for. I figure if I ever get a hankering for a fixed-sight K-frame 3" I can make one up from a 4" M10/64/65 without too much trouble.
Also, I had been referring to my 65 as a "65-3" earlier in this thread; it actually is a 65-5, too many dash-numbers to remember...