any preferences?
4.75" vs 5.5" bbl ?
38/357 vs .45LC ?
not for CAS, just for plinking, field carry, etc
Ruger or Colt?
For Ruger, I don't really care for the Bisley grip. I've owned guns with them from .32 mag through .454 and .480. I think the Bisley grip does reduce recoil but it fouls up balance, pointability, and puts the hammer in an awkward position for fast followup shots. Unless it is absolutely needed to manage extreme recoil (.454, .480), I prefer the standard grips and have sold all of my Ruger Bisleys except the .454.
For Colt, I don't think the Bisley grip helps a bit with recoil and seemingly makes it worse, the only diff is that few cartridge in a Colt generate much recoil in the first place. I think the Bisley grip on a Colt is more mystique than substance.
For field carry, 100%, standard grip for me.
Then barrel length .. I think 5.5" is best overall balancing carrying factors against shooting factors. .38/.357 vs .45 .. depends on what you're shooting at.
I am waiting for Ruger to release some Talo distributor exclusive Blackhawks in .357 / 9mm with a 5.5" barrel. If they manage to put the front sight on top of the barrel so the rear sight is more or less centered when sighted in, it's going to be "perfect." Of the guns currently available, though, I'd nab a 5.5" .45 Blackhawk and not look back.