All in all, the hotel was OK-ish for its category.
My room I was roughly the size of a shoebox (fair enough for the price, I suppose) - however, it was incredibility cold and very drafty (Room No. 33). There seemed to be no insulation and despite a radiator, the heat didn't stay at all. I was super lucky to have brought a hot-water bottle with me, otherwise it wouldn't have been bearable to stay in the room (we're talking early December, around zero degrees Celsius).
The breakfast as ample for the price. The staff at the reception was very nice and helpful - the staff in the breakfast room, not so you much (you got ignored and/or ordered around rather harshly...).
The location of the hotel is probably its best feature. You can reach 3 tube station by foot and a few sightseeing attractions are nearby as well (British Library just around the corner; British Museum as well). It's located in a crescent and it was very quiet at night.
Would I return? No, honestly, I don't think I would. Maybe for a bigger room which is guaranteed not to freeze me solid in winter.