It's a luxury experience with the service and ambience to match.
Perhaps the 2nd best spa I've ever been to. It's quite good.
The food is also among the best, but I've been to quite a few more high end restaurants than spas, so it's harder to rank. Both restaurants are quite good, and even if you only visit the 'secondary' restaurant, Amour Blanc, it will be a highlight of your trip.
Oh, and a salute to the valets who had to work in the pouring rain. Not once did I see them flinch or complain.