I would not stay in this apartment again in the summertime, but I feel sure it would be perfect in the cooler seasons. The décor is beautiful, it is very spacious, the bathrooms and kitchen are very well finished and in perfect condition. Tons of good books on the shelves were a great touch. The location is outstanding, close to many things but still on a quiet street.
A big plus is that we were allowed early check in (our flight arrived at 10 am from the US) and Petr arranged a driver for us at a perfectly reasonable price.
However, in the heat of summer, the apartment is very uncomfortable. Opening the windows resulted in dozens of black flies coming in. When we arrived, it was 90 degrees in Prague and the apartment was terribly hot. There is no AC, nor were there even fans we arrived. Petr did bring us 2 fans, which were a help. He showed us how to position the shades with the window open to let in a little air while keeping out direct sun. This did not keep out flies and left the apartment very dark.
At night, we opened the windows and set a fan in the bedroom window. The temperature dropped enough to sleep comfortably this way. Every morning there were a hundred or more black flies (but they were not the biting kind, just annoying). Each morning, my husband vacuumed the flies up (as they flew around, he got very good at sucking them out of the air with the vacuum wand) and we closed the windows and shades to try to keep it cool during the day.
Overall, an aesthetically lovely apartment that I would highly recommend for a fall, winter or spring stay, but not for a summer stay.