It’s been a few months since I’ve played my R0, partially because of my PRSi. Yesterday I picked it up to practice. To my surprise the guitar was still in tune. It has Kluson deluxe tuners, which are non-locking and a nylon nut, which is not a good nut material. However, it is slotted properly. Locking tuners do not add any tuning stability whatsoever. I like them because they make changing the strings faster and easier. Non-locking tuners do require more skill as there are several methods or techniques of stringing a guitar with non-locking tuners. If you do end up changing tuners, just know that it’s a trivial job. I also think your best bet is to take it to a tech and if possible ask the tech if he/she’s okay with you watching him/her work so you can learn. They are sometimes backed up and you might have to part with your guitar for some days, maybe a week. Your second best option is to watch a bunch of YouTube videos of techs and luthiers teaching how to set up a guitar. After I’ve learned to do these things, some friends started bringing their guitars to me for a set up. I’m payed with beer and jam sessions.