Manhattan Time Service is a godsend! I have used there services twice for two vintage Cartier watches and they have been truly excellent. Owning antique watches can incur costly maintenance. My original quotes from Cartier were three times as much as MTS charged me. Where Cartier was to take upwards of 16 weeks while MTS repaired the inner mechanical workings of my watch, replaced the sapphire crystal, cleaned the watch dial and buffed the case allIn two weeks. They are complete professionals and their work is flawless. Highly recommend!