Hmm. Don't be afraid to get too nerdy with the details. For example, this is what I would have say between my 686-1 and Ruger GP100:
DA trigger pull: both about equal in length, smoothness, and weight. The biggest difference is the Smith has a tiny hitch right before it breaks, whereas the Ruger breaks clean without any notice. I don't prefer one over the other. Both good. I notice the Smith's cylinder locks very early in the pull, whereas the Ruger cylinder locks up almost at the end of the pull. This would be a good indicator of when the trigger is about to break on the GP, except it doesn't occur at the same point, pull-to-pull, even on the same chamber.
Trigger Reset: Smith has this all over the Ruger. The Smith reset is much more positive. Even after dryfiring the Ruger thousands of times, I can still accidentally short-stroke the Ruger when trying to fire very rapidly. (No surprise to me that Jerry Miiculek used a modified 686 to set his world records.)
Single Action Trigger: Smith wins by a mile. Smith has no pre-travel and no effective post-travel. Ruger has a little bit of creep and a little bit of post-travel.
Thumbing the hammer: The Smith is smoother. But it's also seen a lot more rounds. Too early to tell. The GP might smooth out over time.
Cylinder latch: The nod goes to Ruger. The Smith works fine and it just as fast. The GP is just a little eaiser to do. And the checkering on the Smith will chew up my thumb if I hold the gun wrong. I can easily open either gun with just my left hand, while cradling the cylinder. I am curious if the Colt could be operated with left hand, only?
Lockup: Smith wins here. The Smith has a little bit of rotational play in lockup in the CW direction, but it moves back to the same position after you let go. It has very little side-side play. The Ruger has more play rotational play, and it stays where you leave it. I was surprised to find it has just as much or more side-side play, too, despite the double lockup.
Ejection rod: My Smith ejects smoother, but the stupid rod turns out every time I shoot it. I guess I need to buy some locktite.
Aesthetics: I like 'em both, but to me the Ruger wins with the thicker recoil shield and top strap, as well as the shape of the hammer and shroud. The Smith looks more like a snake that swallowed a cow.
Other: My Smith has a restriction just past the forcing cone which is very noticeable with a new bore brush. My Ruger does not.