If you're a solo traveler on a tight budget but want to be close to the Tube and major landmarks then this is your spot. The toilet/shower situation is not ideal (have to go outside the building and into the main hotel and up 2 flights of stairs) but if you're not planning to spend a lot of time in the room then it doesn't really matter.
The river is just a 10 minute walk from the room and then you have a great walk along the bank to Westminster and other major landmarks.
The Pimlico station is very close and there's great food options (pubs, cafes and kebabs) down the street. Easy area to navigate.