For me it's 2 in half hour, and possibly 3 in the hour. When I first started it used to be the opposite, found it difficult to cum in half an hour, now I'm popping my first load when the OWO begins. Need to have a crafty pre-business wank I think.
I do agree though the occasion I only cum once at the end of the punt has the most satisfaction, the teasing and build up makes for a greater spurt