While I don't enjoy MI weather, I'm not sure living in FL would agree with me either. I've been visiting FL about once a year (June, August, September, October and not just WDW) since I was fairly young, 6 or 7, and have always thoroughly enjoyed the vacations there.
I LOVE heat, humidity, the ocean, and the idea of no winter really appeals. I'm originally from west central OH, so having temps in the upper 90s with 90% humidity is something I've lived with all my life. The climate definitely appeals to me; even more so the older I get (44 now). Having WDW in my backyard, figuratively speaking, is appealing BUT--since I'd be a resident, it's not like I'd be on "vacation" when I visit. So, the theme park thing shouldn't even enter into the mix.
What I DISlike about Florida is the "critters". I can't stand the sight of reptiles or amphibians--major heebie jeebies! The thought of needing a "bug service" like we in the north use lawn service just creeps me out. I don't like the grass there--it seems more like fern-type substance than grass. I wouldn't want to live in Orlando, or the immediate vicinity--I've seen the rush hour traffic up and down those highways--NO thanks! It's much worse than Detroit any day.
I'm not sure where we will retire--my husband thinks it would be the cat's jammies to build in Celebration and live this "fantasy" existence for retirement. I don't think I need a "house" at retirement age and not sure about that whole Stepford er, I mean, Celebration thing. I'm not so sure I'd care to be that far from my family. Who knows where our kids will live when they finish their educations, my sister, brother, their families, and my parents are within a couple of hours presently. We will probably compromise and do the retirement condo thing while maintaining a part-time residence here.
Anyway, that's kind of our take on the move thing--another thing to consider is that while you may not consider a move a big deal to kids--statistically, major moves more than twice in their lives has been shown to cause academic disturbances. I know some kids are adaptable, and you would know better than I. I have one who would probably be ok, the other--no way.
BTW, I have a like aged friend who lived in Deltona (near Orlando) and who is originally from MI and returned several years ago. She would go back to FL in a heartbeat. Her husband would NOT. Just a little more information to tuck away.
