We enjoyed our stay at the Mercure Hotel. The location was perfect: 2 minutes walking to Paddington train station and subway, as well as many sightseeings are walking distance. There are many restaurants and bars nearby.
The room was a bit smaller than what we expected, nevertheless quite nice. We did not have warm water for 2 mornings in a row and there was some smell of chlorine when we entered, but nevertheless the staff was extremely nice, tried to help us as much as possible and found a suitable solution.
Even though we think we have spent a bit too much money (but also booked with not too much time in advance) we would suggest this hotel :)