Wasn't sure what it would be like to sleep in a basement level room but I loved it!
It was a little foreign to have a large backlit screen mimicking a window, but once the lights were out the blacked-out room made for a fantastic night's sleep.
The room was modern and clean and had that premium feel to it.
The free buffet breakfast was a great addition, lots of choice for a fully cooked breakfast, pastries, yoghurt, fruit, cereal, juice, coffee etc.
Staff at check in were professional and courteous, there was a good system to keep your bags secure if you get in early and the room isn't ready. They send an email once you can check in.
The proximity to Buckingham Palace and Victoria Station made it super easy to get around.
Highly recommend!