Limit myself to two for a night event or four for a full day festival, I try to keep my rolls at least a month apart in an attempt to stave off tolerance. It would be three months if I had more self control!
Do people get really weak rolls most of the time? Or is the taking multiple pills just indulgent behavior from feeling so good? Personally one good roll is enough for me, trying to re-up later just isn't worth it IMO. And taking more than one at once is completely unnecessary for me as well, I don't think the feeling could even get better.