My watchmaker w/ Rolex parts account is a 3rd generation, well respected jeweler. He's proven himself, at least to me, over and over on all my watches. The price is great, I get to keep the old parts, but he's so damn busy it takes just as long as RSC. Go with who you trust. For me it's my local watchmaker.
Btw, Rolex makes sure he has the training and facilities with random, unannounced visits to inspect his shop. I have a local AD that just lost their service accreditation from Rolex for keeping a sloppy shop and not maintaing Rolex standards.