We were staying at a a well known property brand the week before for work and from the moment we checked in to Keio, honestly, we didn't want to leave. We felt so welcomed by all the staff, front office, housekeeping, food and bev, the chef for breakfast (we had club lounge access)... The list goes on. We absolutely enjoyed every single part of our stay. There are so many very high quality restaurants on site and it's a short 10 minute walk to Shinjuku station but it's still very quiet. We won't stay at any other hotel in Japan now.