We've taken many trips to Edinburgh, most recently for our fourth trip to the Fringe, and this apartment is an easy favorite.
The location is on Holyrood, close enough to everything to walk, but not in the noisy center of things further up on the Royal Mile or along North Bridge/South Bridge/Nicholson Street. There is a Tesco express about a 2-minute walk away and a nice range of restaurants within a 10-minute walk.
The apartment is on the "second floor" which for Americans means the third floor. You have a great view of the Dynamic Earth structure (which is especially nice when illuminated at night) and Arthur's seat. The walk toward the center of town is heavy with buildings for the University of Edinburgh - we always felt safe.
The apartment itself is modern and well furnished. There is a large kitchen and adjacent dining area. The kitchen was equipped with nice silverware and other cooking amenities. There was some coffee and tea there, but assume that you will go shopping for whatever you want on arrival.
There are three decent-sized bedrooms and two baths with shower/bath. The apartment has a balcony and lots of windows for natural light.
There were plenty of plugs, but if you are coming from the US/Canada please consider buying some adapters ahead of time. If not, they are easy to buy in Edinburgh at Boots or one of the many electronic shops in the tourist areas.
We would highly recommend this apartment unless you want it at a time we want to stay there.