When I started working a few years ago, I preferred longer bookings because it seemed to me that this way I would get more money by meeting fewer men. In those days I still was hungry for men's attention and talking to them was pleasant for me. With the time it started to be mentally draining, I felt I was losing more energy from talking than from f*cking.
It is true, as girls mentioned it above - longer bookings (I'm not talking about overnights but about 3--5 hr bookings during the day) attract strange people who want to get to know more about us and to manipulate. I had many problems coming from people who wanted to be close to me.
Now I prefer shorter bookings with new people and touring. People come and go, and hardly remember me. What a relief!