We had a great time in Prague and enjoyed staying in this apartment. It was about a 15/20 minute walk into the centre of the Old Town and had good public transport connections.
The only small things we found were that there was no air conditioning and we really struggled to stay cool at night and the pillows provided were quite uncomfortable to use.
Although out of the hosts control, we also found the building quite noisy - we could hear people being loud through the windows on a couple of nights during our stay and could hear the doors/footsteps through the walls and floors. Might be worth noting if you are a light sleeper!
The host was great and provided lots of useful information before our stay.