I reluctantly looked into changing the tuners on my Masterbilt Zenith but found that the Epiphone tuners aren't just nice looking, they're also quite large compared to other tuners. I checked them against some tuners I had on hand as well as specs from tuners made by the better manufacturers. Most tuners won't do well on this guitar.
So I took the strings off in order to check the tuners out when they aren't under tension from the strings. I discovered that while I had thought I'd had them properly adjusted, some were actually quite loose. I adjusted the tension without strings, trying to get them to where there's a bit of drag but not a lot. If anybody else has been trying to adjust the tensioners with the strings on the instrument, I suggest doing it without strings. It really seems like the only way to get them close to a proper, consistent tension.
When I restrung the guitar, I also changed the way I wrap the strings. I've been playing guitar (not particularly well — ars longa) for sixty years and always felt uncomfortable with having a lot of chaotic wrappings around the posts., but I'd never done anything about it before. So I found and followed this video:
https://www.youtube.com/watch?v=E7O6gQDroog
With the tuners well adjusted and the strings neatly wrapped, I've been much happier with the tuners. I've had a bias for Klusons since I had a beautiful Gibson Les Paul Junior with them a million years ago. I've long since let that guitar go to a friend who actually had some talent, but now I have new Klusons on my other Epiphone acoustic as well as original Klusons on my old Epiphone Olympic solid body, and I'd say the Epiphone tuners are now working comparably to the new Klusons and better than the older ones. I'm sure there are better tuners on the market, but these are pretty good. While I've had the Zenith for around three years, making these changes has restored that new guitar feel when you just can't keep your hands off the instrument.
So my advice is to do your best trying to make sure the Epiphone tuners are set up right before you change them out.