Depends on the girl, you should check the reviews.  I just came back from a 1.5h session with a nice (but not really GFE) and very attractive touring girl and managed 3 nice pops, 2 FS and the last a HJ, all on goal.  Of course, sometimes it's not just the girl's preference but also her ability to manage the session with you, and your ability to keep your stamina up and the supply coming.  Usually I don't pop that often and just maintain my stamina through an entire session.  Sometimes I pop twice if a quick BJ is done first.  This was my first 3-popper in such a short timeframe, which is unexpected since I also had carnal satisfaction earlier in the day.

No little blue V pill for me, I think I have that stuff running through my veins naturally.  In fact, I feel like another round but I have to sleep alone tonight

Has any guy here gone through a marathon day of sessions just to see how much he could dish out?  I might do that some day, schedule with 3 or more providers throughout a single day, possibly crippling myself for a week afterwards.