Hotels without anyone on-site are great until something goes wrong. We had trouble activating our electronic key on our first day there, and the key inactivated on its own the second day. To Anegang's credit, we were easily able to contact the person on call, but each time it took about 20-30 minutes to get the problem taken care of, during which time we were locked out of the building. Also the air conditioning did not work well, which left us hot in a third floor room. Opening the windows helped, but it made the street noise more annoying. Of note, there is no elevator and the stairs are quite steep. If you have any trouble climbing stairs, ask for a 1st floor room.
On the good side, the room was modern and clean.