Keep in mind Berlioz has the benefit of inside information on when to go at the last minute when crowds are expected to be low (and YES that makes me WAY jealous!!!! ) By late September the parks during the day are pretty decent crowd wise, but expect party attendance to be fairly heavy. We were there 9/29 and 10/1 last year. Both parties were fairly well attended, but still quite manageable. Could I have done all Berlioz did? No. But we still had a great time.