I don't have much experience with hostels in London but how much you like staying here depends on your needs I guess.
Pros:
Very cheap, I paid £16pn
The linen was clean
Each bed has a proper lockable cage, light, socket etc.
Free wifi that's easy to get into
Cons:
The shower was incredibly small without a proper place to get changed or dry properly
There's no locks on the doors of the toilet or the shower
The sink is within the room, so not ideal if you wanted to shave etc
The hang out space is very basic, without cutlery, plates, glasses etc
The breakfast was pretty basic even for £4, I'd consider breakfast elsewhere
But I guess you get what you pay for, and depends what your priorities are.