Positives: I can see just the location. Despite not in the touristic circuit, it is just behind the Hyde Park, from where you can get a bus or a metro to downtown very easily. And in the parallel street you can find many options of restaurants, snack bars and small supermarkets. To be fair, the german girl who works there is very kind and helpfull.
The negatives: The room is very small, the bathroom is incredibly tiny, there is no minibar in the room, the safe is the smallest I've ever seen, the wardrobe is a joke (fits just very few clothes), there is no service in the apart-hotel, there is no lift and the stair is very hard, If you arrive late, you have to get the key in another hotel in the parallel street.
Well, I really don't recomend, unless you are just worried about the price.More