We stayed for a long weekend with 2 other guests. the space was more than adequate for this. the location could not have been better with close proximity to everything, in fairness Edinburgh is a very pedestrian friendly city, but the location was still notable as a positive.
the flat was clean, spacious and perfectly well equipped for a weekend break, or longer. I would not hesitate to live here, big rooms, space to stretch your legs etc.
I would summarise by saying, if you're looking for central self catering in a spacious clean apartment, don't hesitate to book. keep it simple!