Not all Klusons are created equal. The original ones are mostly junk, while the current Kluson-styled Gibson Deluxe tuners are actually two different tuners. The 10mm screw-in version that Gibson uses on a lot of the USA line varies from mediocre to awful. The stock tuners on my 2007 SG Standard were awful; the posts wobbled and it just would not stay in tune. OTOH the tuners on my 2007 ES-335 Fatneck have 11/32" push-in bushings and they've been nothing short of amazing. The Bigsby on that guitar holds tune without a roller bridge. I'm not sure who owns the trademark for the new Kluson-branded tuners, and I've yet to try those.
The tuners are a small part of that reason. The bridge string slots and nut slots being cut correctly are a much bigger factor. Good tuners help in stability, but without the nut and saddles being cut right, nothing will stay in tune with the best tuners.