Flawless in absolutely every sense.
The hotel itself is a gorgeous design, impeccably clean, and very comfortable. The gym is the largest/best in a hotel l've ever seen, the pool is perfectly maintained, and sauna was just excellent. The room design is beautiful and I think perhaps the most comfortable hotel bed I've ever slept in. The blackout curtains do their job perfectly (had absolutely no idea what time of day it was when I awoke).
For dining, the breakfast was among the most impressive of any hotel I've seen. Not only the sheer variety, but quality of every item was amazing. Maru, the cafe, has a wonderful wine list and the burger was delicious.
Even it every single one of the remarks above wasn't true, it would still be a 11/10 stay due to the service. I feel confident that any single member of the staff could successfully run their own hotel based on the level of excellence I experienced. The coordination among staff to have bags seamlessly taken from room to storage to taxi saved valuable time, effort, and energy during a short trip. No request is met with "I'm not sure" or "this is the wrong department", but "yes of course" to the point that it feels the entire staff is working the same job: to ensure the guest has a perfect stay.
They succeeded.