Doug's flat is a fantastic base for a trip to Edinburgh. It is fantastically well located - a short walk from the train station, in the heart of New Town. You could eat and drink fantastically without ever leaving Thistle Street! It's also within easy walking distance of several attractions - the castle, museums, Dean village etc., and a pleasant (if longer) walk to Holyrood and Arthur's seat.
The flat is very stylishly decorated and is a calming and comfortable place to return to. The bathroom is small but has a good shower, and we had no issues with hot water. The flat is very cosy - we actually had to turn the heating down (a surprise for Edinburgh in early March!).
There was quite a lot of noise from the street. This is to be expected given the (excellent) central location, but worth bearing in mind for light sleepers - though it didn't bother us at all.