No booking is ever going to be 100% risk free and whether there is security on duty or not is not going to stop something happening to you in a bedroom within a hotel.
I do find hotels safer than private homes though; the perception that there are other people around that can intervene is psychologically there and may cause a client to hesitate before doing something. In addition, the hotel has their booking details which makes them more traceable in the event of an incident.
I am outcall only and I far prefer hotel outcall appointments. There is a minimum standard of cleanliness/lack of clutter/facilities that you can rely on compared to the occasional hovel a client lives in.