I just bought a 642-2 to be carried as a 'Doomsday' device... not as a plinker. I will continue dry-firing it. I did remove the sideplate and clean & lube it. I have other S&W's I have re-sprung - they are 'fun' guns. Comparing my well broken-in K-frame snubby, a 2" 10 made 1/03, reveals a night and day difference. The all-stock 10 has a far better trigger than I assume the J-frame will ever develop. In my mind, that makes the 642 a better choice for pocket carry... a lower probability of an AD upon rapid retrieval. Of course, the suspenders I needed for the 2" 10's carry in a pocket can be left home, too - that beast literally weighs in at twice what the 642 does. Even fitted, as it is now, with wood service boots, it is much more comfortable to shoot. That itty bitty J-frame boot grip takes the 642 out of the comfort zone for me... of course, a larger grip would keep it out of my pocket, too.
I agree that S&W must be p.c. in their offerings - here this simply means they will go 'Bang!' with anyone's ammo - anytime - under any state of cleanliness. That means a stronger than what I care for hammer and return spring. Of course, my homebrew ammo uses Federal primers - for lite springs. But... I only use commercial ammo for carry - specifically, the Rem R38S12 158gr +P LHPSWC in .38. I have to insure reliable ignition, so the OEM hammer spring stays.
I do have a means to make the stock 642 trigger to 'appear' lighter... I'll take my 1895 Nagants, resplendent in their 20+lb triggers, to the range with the 642 - and shoot them first. The 642's will feel 'great' after that! Seriously, my Nagants are plinkers... the 642 isn't. Seriously, in one of those infamous 'fecal matter impacting the air movement device' situations, it is unlikely you would notice the trigger effort. Just take it to the range as a shooter, for familiarization, every month or two or three, and keep it clean, stoked, and with you - ready for that 'Doomsda', should it arise.
Stainz
PS Gotta admit - this is the first S&W I've acquired that didn't get at least a new grip... much less some springs!