I usually start off with one because I perform and last longer if I am really hard, and then move onto some various positions, a bit of a blow there in between and then at the end I finish off with one. I usually find that if I can control how fast the WG is giving me a BJ to "prep" me for the session then I am a lot more in control during penetration, few days ago I was punting with my, now called "regular" and I blew my load over her face for the first time, it was priceless.