I would come back just for the location alone. You're in the heart of Covent Garden, which is about as safe and as central as you can get. The Covent Garden tube station is literally a three minute walk away. Other stations - Leicester Square, Piccadilly Circus, Charing Cross, Tottenham Court Road - are all within walking distance. It's ridiculously convenient.
Even though the apartment's on a busy street, the bedroom is tucked away (as mentioned in the Air BnB listing) so you're shielded from the noise. I booked this place for the kitchen, but never ended up using it. It's all functional, though - I'm sure if you were determined to cook, you'd have no problem. The fridge is small but can store quite a bit in spite of its size.
Someone mentioned this in an earlier review, but the bathroom does not have a power socket near the mirror. I worked around this by doing my hair in the kitchen, using the oven's reflective door as a mirror. I'm sure some people would be put off by this, but I didn't mind it.
Toby is a hands-off host, which is what I prefer since I value privacy. He checked in with me throughout my trip to make sure I was ok, but otherwise left me to my own devices.