I'm noticing that some of the Colt copy variants have a thicker grip portion where it meets the backstrap and these are the guns I prefer. The Pietta Model 1851 London .36 Caliber Revolver is one such pistol with the thicker wood grip. This appears to be due, in part, to a different backstrap profile, but I like it nonetheless.
The Pietta 1862 Police .36 with 5" barrel is nice and is six shot as well, so it really isn't 'correct' in that I do not recall Colt making a police on the larger 1851 frame, but it certainly looks cool.
I'm not sure about buying these ASM's even though they are unfired and in perfect condition, unless, perhaps, I had the internals reworked...