The management of Tamu (and Anaya - they are same management apparently) seems more interested in revenue maximization than guest experience as a first priority.
In summary, there're better choices in Koh Rong and I DO NOT recommend staying in this overpriced place.
I mean the beach & sea are the same, and in my stay, I did not see any differentiation of services or facilities to justify the much higher prices.
And the exorbitant room rate seems not enough for Tamu:
I stayed on a New Yr eve and was expecting a positive experience to welcome the new year. However, they decided to combine all guests of Anaya and Tamu for a "New Year" dinner which is USD40 per pax (almost half of the room rate if you count 2 pax)
Now money is really not a problem if they pre-communicate about this plan early, respect and give their guests a choice: you can go another place for dinner if you are not willing to pay.
The trick is: this place is secluded and the next town or eating place is a few Km away, and they just told me right at dinner time about this plan i.e. you don't have any choice at all.
This kind of entrapment really left a bad taste in my mouth.
Another advice is to check the sea conditions; in Dec the sea was very rough in Tamu side of the island. This was not the case when I went another part of the island - Oh and to go another part you have to rent a motorbike from Tamu which is US$20 a day.
Be warned friends, these are hidden costs and you might be trapped