If only the Anantara were in a good location it would be a clear winner after Aman for within town.

I can't say I particularly liked either (Belmond or Park Hyatt) very much - if I had to go back and pick, I'd probably go Park Hyatt; but I always feel like a good pool is essential for a Siem Reap trip, and Park Hyatt has the opposite of a good pool.

Either way, be prepared for bus loads of tourists as both hotels take on huge bookings.