The area, Bahnhofsviertel, is not the most pleasant in Frankfurt, but, at least, during daylight hours it felt reasonably safe.
The inside of the hotel, in contrast with the neighbourhood, was surprisingly spotless.
The luggage storage didn't feel sufficiently safe to me as the bag was to be left right by the reception desk, not locked away somewhere, which, given some of the characters around the area, didn't seem a good idea. I chose to keep my stuff in a locker in the Hauptbahnhof even if I had to pay a fee for it.