We went with a group of friends to Mussoorie this winter, in the mood for relaxation and lots of fun, and in the process found this hidden gem that is now our go-to hotel for our vacations. In fact, I might pick Mussoorie over Nainital just because of the Carlton. Nainital is nice (I always go as a pack of young folks), but I haven't found a hotel as relaxing, with such tasty food, huge rooms (try playing cards or Tripoli with 6 friends in a regular hotel room), great service, and amazing ambience.
I normally stay at 5-stars (thanks expense account!) for business travel around Asia, and while they're great, don't have any 'feel' to them. So instead of the Jaypee in Mussoorie, I picked the Carlton for our trip, after reading the reviews on Tripadvisor. In hindsight, a very good choice!