All good points!

I bring this up because I believe it's worth knowing.

"4) The M65 doesn't have the full under-lug (except for the "Ladysmith" version) and so it is lighter and trimmer than the M66"

On this point, I believe there's more to say.

I have a Model 13 which is the blued version of the 65. When I compare them side by side, the model 13/65 bull barrel is considerably thicker than the Ladysmith barrel - considerably.

The extra steel of the ejector rod shroud and the thinner barrel of the Ladysmith 65, to my eye anyway, somewhat evens things out. The weight of the ERS being closer to the cylinder than the extra weight of the bull barrel extending all the way to the muzzle could make a case for the Ladysmith being more point-able.

By the same token, with the weight closer to the cylinder on the Ladysmith, the bull barrel version might be more stable with recoil.