My husband and I booked a cruise with them. Everything was fine until we came back. We are Gold members of the Princess Captain's Circle now, but Cruisemaster hasn't managed to update our online profile for 9 weeks now (3 emails from my side maybe not enough?) Since you can't do it yourself and it's not possible to contact Princess Cruises by mail ('Whoops, page not found') because you have to go through the local agency, I would not recommend to book with cruisemaster - at least not if you consider making more than one cruise with the same cruiseline.
Had an amazing experience booking my Western Europe cruise with Cruise Master. The team is extremely helpful and well versed with everything to do with cruising. The best part is that they still keep in touch with me, even though I have already returned from my vacation. Would recommend Cruise Master to anyone looking for best service and consultation wrt cruising