Overall our stay was excellent, for a new luxury hotel the Angsana does a lot of things right, but there are a few growing pains that can be observed across a few areas.
First the plusses:
Food: some of the best meals we have had. The nightly dinner in particular was always spectacular, featuring a 3 course menu (with several choices), rivalling any upscale meal in London, Paris, etc.. Even snacks at the pool bar restaurant all prepared very fresh and delicious. Breakfast always good.
Spa: the spa suite package includes 90 minute massage every day, a very good deal. Well trained massage therapists. Out of 8 total massages, 7 were outstanding. Excellent facilities, including a large massage pool, hammam, and sauna.
Grounds and Suite: beautiful surroundings, picturesque beach and pool areas, overall idyllic setting. Beach quite nice. Staff bend over backwards to bring towels, serve drinks, etc, making you feel very comfortable and looked after.
Other areas that were generally good, although could use some improvement if Angsana wants to truly be at the top of the 5 star rankings:
Bar and Food staff: many were quite good (Ramesh stands out as one of the kindest staff at the hotel). A few were poorly trained, forgot orders, and one or two were even unpleasant / clearly not enjoying their job.
Maintenance issues: somewhat to be expected from a new hotel, there were a few occasional maintenance issues, although none were terrible. Power in suite and AC went out one night, shower in bathroom didn't drain very well, various bits of (minor) construction going on here and there.
suite design: in suite pool quite cold, in shade all day, no privacy, especially if you have a spa suite on the ground level (maybe this not an issue at spa suites on upper levels?)
Boat House: the team manning the stand were very accommodating and friendly. The staff member who drove the boats was unfriendly and not so skilled. On the first day, he ran the ski boat up onto a coral reef near the shore, and on the second day, he took us snorkelling in the middle of fisherman's nets which created quite a scene with some local fisherman we unexpectedly got caught up in the middle of.
sun Screen: with a resort like this, we expected to have sunscreen on site (either for purchase or generally available). After being told (and looking) several times, we finally found out the shop was out. The assistant manager sent someone to get some for us from town, but then came and found us in the beach and put us in the hotel car (for free) to get it ourselves from a mall 15 minutes away.
In summary, a very nice resort, we would consider coming back for a return visit. To justify a premium price and reach the quality / service levels of other comparable resorts (eg Maldives), a few improvements need to be made as noted above.