(Note: We stayed here in March 2010 but there is no 2010 option in the drop-down menu!)
My boyfriend and I stayed at Acaya upon the recommendation of a friend of his. We called relatively late to make a reservation, so the only room available was the most basic room.
We did not have a car, which made getting into Las Terrenas a bit frustrating. The hotel was able to recommend a reliable motoconcho, but for 2 people, twice a day, the cost built up. Renting a car or 4-wheeler might be a good idea if you are considering spending any time in Las Terrenas as well as Playa Bonita.
The room itself was, indeed, very basic. A full sized bed and shelves (not drawers) for the clothes. When we arrived, the bathroom counter was dirty (although the rest of the bathroom was clean and we did not have problems with the cleaning afterwards). There was no A/C since it was a basic room, but we did not need it at all.
The room was a bit run-down, as if it were last on the list of rooms to be updated. The fixtures were rusted, the shower curtain was falling off the rod, and some of the lights on the porch and inside the room did not work.
The reason we stayed was the amazing view of the beach. The beach was clean and right across the road. The hotel has put out chairs for guests and provided beach towels. The breakfast was also good and hearty. The staff was very nice and the new French owner came around and introduced himself and chatted every day. We got a discount for paying in cash as opposed to a credit card.