Oh boy, I bet that May in Cancun was pretty darn hot! It's still nice though being on the water but if the breeze dies... it's really muggy. Acapulco in November would be beautiful weather and August in the DF would not be bad, hot but dry. Mexico is a wonderful country, like everywhere there are problems but the country is so diverse, so much natural beauty and so many wonderful people. I like to travel but I can't imagine wanting to live anywhere else.