The apartment is nice, quiet, and very easy get work done in. The internet connection worked flawlessly. Margret was available if I needed anything, but there were no issues during my stay. The location is simply amazing. The view of the castle right outside the front gate is breathtaking, and Grassmarket is very central for sightseeing. I highly recommend staying at the castle apartment, and I would book it again if I am back in Edinburgh and it is available.
Thanks for everything, Margret!