Any action job on a revolver performs EXACTLY the same function as shooting it--with the exception of changing the springs.
That may be true in some cases, but it depends on how good the trigger pull was to begin with. If the trigger is loaded with creep and has a sloppy, inconsistent letoff, use won't make too much (if any) difference. I have a S&W 686 with thousands trigger pulls on her (both live fire and dry) and the DA trigger is still not that great. Not what I would call "mediocre", but not much better honestly. It has noticeable creep, the pull itself is rough and the let off is junky with a lot of overtravel. And I do remove the sideplate and clean it out/relube it every 500 rounds.
I also have a '59 M17-0 K-22 with a trigger that I would describe as "good". Not "excellent" or "superb". It doesn't have any creep, and the pull is reasonably smooth, but the let off isn't that great. And only God knows how many rounds that gun has seen.
Back to the OP's question though. It depends on how good of a trigger pull you want. The average action job will cost $150, give or take $50. A good action job isn't just about spring swapping. All spring swapping will do is lighten the pull. A lighter pull masks other crap that might not be right with it. Sure, my Springer 1911 had a light SA pull out of the box. But it was junk otherwise. In addition to polishing the appropriate contact/friction points, the "timing" of the lockwork (for lack of a better term) will need to be fine tuned. I guess you could call it fine tuning/fitting of each individual component so that everything works together perfectly, like a fine watch. If you want a pull that breaks like a glass rod, and is velvety smooth like a pre-war Smith or Colt, expect to shell out $300 plus. That's the kind of feel I want for my Smiths. Makes me misty eyed just thinking about it
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Again, it just depends on what you are looking for. Do you want the Chevy or the Caddy?
I've had an action job performed on my 1911, as it had the lousiest trigger of any of my handguns. And lousy is being kind. It was definitely worth the money. Before the trigger job, I could only muster 6" groups at 7 yards. Now I can make a big ragged hole at the same distance if I do my part. 3" groups are more common (unsupported). My 686 will be next, followed by my 642. I just have a lot of other things going on that are eating at my budget right now.