Nice specious flat with everything you may need even for a longer stay. Great location and really friendly and helpful hosts. Quiet yet walking distance to town's centre and Charles' Bridge. Modern with futon beds surprisingly comfortable. Not much wardrobe space.
Two things not ideal, if this is of your concern: the floor is very squeaky in one of the bedrooms and the flat could have been cleaner, but this hasn't affected us (6 girls staying for a long weekend). Would definitely recommend and go back.