We are looking to go to US, IOA and Seaworld either the 1st week in Oct. or the 1st week in Dec. I had opted for Oct. just because the Dec. weather is so unpredictable and I don't relish the idea of getting soaked in 60 degree weather. Also , my girls have off from school on the 6th, so they would miss 4 days vs. 5 days of school. Now I'm wondering, are the crowds much different at the two times? If there will be crowds and long lines in Oct., I may opt to go in Dec. instead. Any opinions?