We were 4 people and the flat was perfect for us, enough place, very clean and situated perfectly. (It´s just about 5-10 minutes to Charle´s Bridge by feet!)
Check-in was very easy although we were a bit latter than we announced. The price also was very good for the flat, so all in all I can recommend this flat for young people like us and I think also families would have a nice stay! :)