I sorta like locking tuners but I do like to get at least 1 or 2 turns on them. I have had problems with breaking strings at the tuner (while playing the guitar not on initial tuning) when I just pull the string through and lock it.
May well be user error but that's my experience. The tuners I got are locking sperzels
If they are good tuners with no issues, then they will last for the life of the guitar.
Fender schaller circa 1990 vintage - no issues but a bit sloppy in the gear mesh
Sperzel - 2 have stiff points during the rotation. Carvin sent me 2 new ones, then another developed the same issue. So 3 out of 9 were bad. 2002 vintage. 12:1 ratio is not fine enough for adjustments on the fat strings.
Planet waves auto trim - 18:1 ratio. They cut the string ends as you turn! I love these!!
My feeling is this: if you are buying new tuners, spend the 20 or 30 extra bucks for lockers. Yes, you can wind the stings around regular ones and have no issues, but lockers take a half to 1 full rotation to get to tune
I have 16 yr old sperzels and never had an issue. I also have the Fender/Charvel ones and a set of the Suhr's. If the tuners themselves are of good quality there's no issues. And in terms of added mechanical complexity it's extremely minimal and couldn't be any simpler
I love them for quick string changes in a live setting. They let me bring 1 guitar instead of 2 to a show. I don’t put them on guitars I rarely gig with.
A builder friend swears by Hipshot tuners, so I bet those have a very good lifespan.