I have a 2007 ES-339 that I bought used about 9 months ago. The person I bought it from (Ebay) evidently, never played it as it seemed to have the original strings on it when I got it. Anyway, for such a great guitar, it never stayed in tune and I had issues with the G string slipping. I tried a new set up, 2X to the luthier for neck adjustments, nut carving, saddle work, lube, nut juice etc. Nothing worked Finally, I took out the Deluxe tuners and dropped in a set of Gold Grovers. Immediately the guitar stayed in tune, no longer has any problems with slippage and, I think it helps the sustain with the added weight. It certainly feels more balanced.
Recently, I changed out the bridge for a Gold one and added a TP-6 for better intonation. Both pieces were taken from an ES-336 and fit perfectly without any alterations. The guitar plays flawlessly now. I can put it in the case for a week and when I take it out it is perfectly in tune.
I know a lot of people say those Deluxe tuners are fine and point to other issues when it comes to tuning but, with my ES-333, my Les Pauls and my SG (to a lesser degree) I have always had tuning problems with the Deluxe tuners and it has always been solved perfectly with the addition of Grovers. Just my opinion. I mean, how many set-ups and neck adjustments should a relatively new and in good condition guitar have to go through in order to get the tuning issues resolved?