I booked well in advance based on the locale (Bloomsbury), positive reviews, and bargain pricing compared to other area hotels. My room was a twin bed single + ensuite. Compact. No room for a desk, chair, wardrobe or such if that's what you need, but was fine with me. Bathroom is small but ok, but the shower leaves no elbow room (it has one of those rain heads, but there's no escaping it in this skinny phonebooth, so you have to turn it off to wash and shampoo, then back on again to rinse).
Considering the location, it was quieter than I expected -- even with the windows open, as Gower St isn't a major thoroughfare and has no bus service. Buses are a couple short blocks away, as is the Goodge Tube Station (the Russell Square station and big Euston hub are each a half-mile away). The British Museum is just a 5-minute walk down the street, the Dickens' Museum twice that, while Covent Garden, Piccadilly Circus, Soho, Carnaby St, Regents Park and more all within a 15-20 minute walk.
A full English breakfast is included every morning, plus help yourself to a bowl of fresh fruit, cereals, coffee, tea, OJ, etc. That'll save you a good 15-20 quid or more per day otherwise. Wifi was fast, but there were a couple brief outages while I was there, probably their ISP to blame, so out of their hands. There is no elevator, but someone is available to lug your luggage up or down if need be. Also no A/C, although the house will provide a fan if needed.
Stayed 5 nights, would so again.