I have a model 60 (the stainless version of the 36); it's a 2" round butt. I would rather it be a 3". It would be more shootable. But it's a good little piece either way. The round butt conceals better. The square butt fits in larger hands better. For concealment's sake, I always go with the round butt for smaller revolvers (my hands aren't big).
I load 9mm, 10mm, 38 Short Colt, 38 Spl, 357 Mag, 44 Spl, 44 Mag, & 45 ACP.