We booked one of the hotel rooms for 3 nights in September.
We enjoyed the friendly staff , the food, the driver they organized for a car for us went out of his way to be helpful although he was used to having a guide with him to translate his English was good enough for us to communicate. They upgraded us for the last two nights to a suite at no charge as the air conditioning in our room didn't work very well which was very nice of them and the suite was light and airy.
We ate all of our meals at the hotel as we were still a bit jet lagged and enjoyed them all. They were not really great but was fine. The selection was a bit limited, but it was our choice not to go out.
What we didn't like was the hotel room was very dark and noisier than the suite, and we felt the room was getting a bit tired. After our hotel room in Bangkok - which was larger, brighter and had better pillows and was cost a bit less -, we did not think it was great value for money. Plus the BED WAS HARD in both the hotel room and the suite. They are pedestal beds with a mattress on a hard surface. These are not soft mattresses and they are all the same in all the rooms. The suite is open plan. No door on the shower but a door on the toilet, so you need to be ok with whoever you are with.
The wait staff in the restaurant had just enough English to take orders, but not enough for anything complicated - like 'I only want one egg and no potatoes' If you get the eggs from the menu, you get everything in the egg order.
Just an extra tip. My Other Half converted some money into Cambodian Riel - DO NOT DO THIS - no one wants anything but US Dollars.

We are a group of New Zealanders who stayed for three days at Heritage Suites. While we stayed in the hotel rooms, rather than the suites, we could not fault the service, ambience, kindness of staff and cleanliness. Everything was just as we would have asked for.
Staff went out of their way to be helpful and the food was great.
The hotel is small which adds to its charm. I don't know how many suites, but there seemed to be only around ten hotel rooms. So we were not crowded at any time
The amenities are as good a expected, lovely pool with plenty of recliners and well attended bar.
We would certainly stay here again if we were in Siem Reap again.
Overall, the Siem Reap experience was excellent, and far better than expected.