I too would like to echo the sentiment above about the unpleasant response. Flyertalkers are generally much more cordial.

I've been to Kyushu several times in June and July, and looking back at those photos, they don't seem too much different from when I visited during other months (January, April May, October, November).

I will say that Kagoshima is a long way from Fukuoka, and I certainly wouldn't do it as a daytrip myself. But this is because I love Kagoshima and can spend days there. If you like aquariums, they have one of the most unique ones where dolphins are let out into the canals (are they canals?)