The hotel may be a bit old and some of the rooms may look rundown, but the room is actually pretty clean and spacious. The location is excellent, easy access to both Shinjuku and Shinjuku sanchome station. In addition, the service is amazing. The staff are all friendly and they will provide you with your requests as much as possible.
There was an issue with one of the ACs but the hotel fixed it quickly (there are many ACs so even if one is broken it doesn’t really matter).
We needed to extend our stay at this hotel, but the same room we already booked wasn't available on the extended day. So we booked a different room, which meant we would have to pack up and checkout once to move to the other room.
Without our knowledge, the hotel actually negotiated with the other guest if we can switch rooms so we don't have to move out of our original room anymore. Talk about hospitality at its finest.
There is a bit of noise at night (mostly police cars and ambulances) perhaps because it is right at the edge of an entertainment district. But overall the friendly staff, the nice room, and the great location outweighs the downside unless you would have sleep issues with noise at night.