I bought an Omega Constellation (168.005, cal 561) at auction, but it was running terribly fast. Having looked through these forums, I decided to send it off to Brendan (webwatchmaker.com) for a service.
I couldn't be more pleased with the result - Brendan's communication was great, keeping me informed as the service proceeded and asking before doing any extra work - including WhatsApping photos for a quick response. Very reasonable price, too.
From my experience, I'd certainly recommend Brendan. He also returned both the replaced crown and crystal.
Will try to post photos when I work out how!
Hope that is helpful to anyone considering having their watch serviced.