Niko's place is very spacious and nice. It is pretty convenient for a trip to Prague, but it is not "5 minutes from the city center." It took us 40 minutes to get across the bridge while walking and 10-15 minutes driving or by transport when we took uber or the tram.
The host never introduced himself, which we found a little odd because he seemed to have guests over every day. There were several people in the apartment who we never met and were not the other couple who arrived the same day to stay in the other room. Occasionally these people were noisy. Overall it was alright.