We had a 2 night stay at Flower, and i wish we had found this place at the beginning of our Vietnam trip. We stayed at another hostel before this, and it did not compare.
Staying here felt more like a hotel/homestay rather than a hostel. We had a HUGE room, with a HUGE bed which was fine, TV, AC, Fan, hotel grade bathroom with a great shower, charging plugs by each side of the bed and hooks (hooks are the best...they are so underrated!).
The staff or family I should call them were exceptionally lovely and welcoming, even if their english was not hugely perfect.
Only downfalls of this place were the construction that started at 7am and the cigarette smoke (from the construction site) that came through the fan in the bathroom, even if the door was shut.
Definitely recommend for a quiet Hanoi stay!