Tuners
I've always been in love with Grovers (the high ratio ones, not the lower ratio ones that ship with a lot of asian guitars). I have them on my dreadnaught and they're perfect. My electrics have Schaller tuners which also work fine.
I'm not a fan of the Gotoh tuners, though it wouldn't surprise me if they have a model that is comparable with the other two. I've never gotten into the whole Spertzel Locking Tuner idea, though I understand that the shredders really like'em.
Jeff