We were in London for a friends event and knowing we would be back very early in the morning, it was a cheap way to put our bags somewhere and sleep for a couple of hours. I would say that overall the bathrooms were very clean and bedrooms again were clean but we did have an issue with a few bits of rubbish and someone smelling like weed. That is not however the pub/ hostel owners fault.
Its perfect location just next door to the tube station and you can have a drink downstairs. I have stayed in many hostels and I would say this is one of the cleanest.