This is a fantastic apartment. It's a great location to explore Edinburgh - we had a place to get good morning coffee a minute's walk away, and a huge choice of pubs and restaurants within a few minutes walk, including good family-friendly options a short walk up the hill. Also a handy walk to Tesco/Sainsbury express stores for other bits and pieces.
The apartment is really well set up with everything you need. We were travelling with my two children (6 and 3) and they loved all the toys and the bunks and other children's things that just made everything easy and them feel at home. We were there for a week so having all the cooking and laundry facilities was great - and the beds are nice and comfy.
Haymarket Station is about 5 minutes walk away for easy access to transport. We also found the walk into central town (around Waverley Station) a lot shorter than expected - about 20 minutes at a decent pace - so we did that several times rather than using public transport. As pointed out in the apartment description, it's on a busy street in the centre of town, so there's noise from the street in the front bedroom, but can be dealt with by ear-plugs. We'd definitely recommend, and would stay again.