Nice apartment in a really great location, some good recommendations of things to do and places to eat in the guest book, and I really liked that the hosts left out a travel guide and city map to help get around.
The bed was comfortable and the apartment was spacious enough for two, although the lack of a table to sit at and eat from (they only have a low coffee table) was a little annoying.
The place itself was a bit shabbier than expected, although it had definitely been cleaned, it didn't feel that clean inside. Also the shower is really short so not that comfortable. In general I would say it felt a bit too much like the hosts have done this a million times before and so didn't really care about the guests, they had minimal contact and just copy-and-pasted messages. It didn't have the human touch that I like so much with AirBnbs.
Overall, though, it's a nice place in a great location with lots of tips from other guests about things to do. Perfect for a short stay where you just want to get out and see Edinburgh.