Stamford Street apartments have the best location in the heart of London, right across the road from the Waterloo campus and just across the bridge from the Strand campus. However, they are small and have a more private feel with not much going on. Once a month there was a pub quiz for students but that's it. The room was small but nice, every room had a private fridge, desk and two chairs, and private bathroom. Kitchen was shared and had a small TV.
Great Dover Street apartments were much bigger, close to the Guys campus but further away from the Strand and Waterloo campuses. All the parties were going on there, there were more amenities and they offered cheap breakfast as well. Rooms were similar to Stamford Street apartments, a bit bigger and with private bathrooms as well.
Hampstead residence was far away from all the campuses (30 minute ride on the underground), rooms were bigger but with shared bathrooms.
I haven't visited any other residences.