We traded one of our Marriott weeks into the 4Seasons.
It is one of the nicest timeshares that I have ever stayed in. The service was phenominal. The unit needed some refurbishment, but they said that would be done shortly.
The hotel is about 1/4 mile from the farthest units, but it's a nice walk, and they do a great job with service by the pool.
Kid's program is included. Could barely pull my son away from the video game room, also free.
The concierge service was great, even getting us a private plane charter over the Grand Canyon for a very reasonable rate.
It will be a hard trade, but the weeks are out there.
4S mainly was selling it as a fractional, but they sell single weeks as well.