everyone has their own preference, I like November as the crowds are considerably less plentiful. I believe it is technically still hurricane season and you could possibly run into some bad weather. It does get more crowded closer to Thanksgiving and prices tend to rise. Lobster season runs from June through Feb 14, so no matter what time you are there in Nov it's Lobster Season! Truth is, especially if it is your first trip, you will have a great time no matter when you go!