It's a bit pricey for a hostel but this was my favourite hostel after travelling for 5 weeks in Europe. It is clean, the staff are friendly, the wifi is good, the breakfast is good, the beds are comfy. You don't have to pay extra to borrow padlocks or use the lockers in front of the lobby counter. It's only a few stops away from Picadilly Circus via the Central Line. Nearest Underground is Queensway (127 steps down to the platform if you don't want to wait for the lift!) and Bayswater.
Stayed for two nights here in the 10 bed mixed room. 10 beds = two triple decker beds + two double decker beds in a 5x5 meter room. Very very cramped room. Rooms are locked using number combination locks. No keys. Lockers are small. There's one bath, one toilet and one bath toilet to share with everyone. Wifi is good. Distance from the nearest Underground (Edgware Road) is good. Walking distance from the London Central Mosque.
Quite a walking distance from the nearest Metro, nearest Metro not exactly near the city center too. But only a few stops away from the stop to the train that will take you to Palais Versaille. Staff is good, breakfast is acceptable (croissants are amazing!), lift was broken (had to lug all my stuff to the 5th floor! Lockers won't be able to fit an entire luggage, only your valuables.
Stayed only for one night. Lost my external battery pack charger here. Lockers are small. The Eiffel Tower is within view of the hostel, but it is no where near the hostel (it is quite a walk away!).
Wifi only at lobby. Laundry is free! Lockers are quite big (bring your own padlock!). Beds are comfy with reading light. Breakfast is good. Walking distance from city center. Staff is approachable.
Huge lockers, good wifi, good security, a bit tucked away from the center of the city, but not too bad. Very clean, breakfast is good too. Floorboards are creaky though.