The benefit of going at that time of year is many schools are already back in session. Our first trip to Disney was in August and although it was very hot, crowds were not significant. You also still may have the benefit of the parks being open late. I know that they do change the schedule sometime in August, but I can't recall how far into the month. We used early entry, with a mid-day break, then finishing up the day in another park to avoid the hottest times of the day.