"The good parts:
The front desk staff were very helpful when I needed to call the airline on a local Japanese telephone number, allowing me to use the front desk phone without charge.
The location is convenient for this price point. There is an underground passageway from Shinjuku station straight to the hotel, open until 23:00. (Though difficult to find, looking for the entrance to the Shinjuku subway line should put you in the right tunnel)
There are convenience stores and restaurants in the same building.
Not so great stuff:
The rooms are small, even by Tokyo standards the space to move around the bed is tight.
The rooms are not even slightly sound proof. It sounds like they put up standard stud walls with simple plasterboard. You can hear people in other rooms talking, snoring and banging around.
They give you ONE low quality pillow upon checkin. You want more pillows? They put a small amount more in the corridor each day for first come first served. Reception simply tells you to check there.
The TV is the worst hotel TV I have seen in a long time.
The toilet is unnecessarily LOUD! Sit down? LOUD. Flush? LOUD. Refilling the tank? LOUD. I have never come across a toilet this unnecessarily loud.
The provide one medium sized towel and one hand towel. You can put a sign on the door to just provide a new set. But they will come in after 3 days, clean and remove any extras.
The laundry room is far too small for this size if hotel. It needs to be twice the size."