Fortunately I also live in the south and roads around here are also, for the most part, pretty smooth. I think I am going to go with the M Sport though if only for the combo of the aesthetics and interior details.
DB, I have considered waiting on the 4 series but I'm a little worried about residuals since right now the 328i coupe has such a high one combined with the $2250 in incentives. That's a substantial enough difference that for me, it could make it a do or don't kind of deal. If the 4 comes out with a 57% residual and no incentives, assuming it'll have a higher base price than the current 3 coupe, then it'll probably be out of my range. Well, I should say out of my range unless I was to order a stripper. It is a tough call though! I wonder if they'll offer a 420, 428, and 435 (or whatever equivalent)?
2017 i3 REx
2013 E92 328i
2017 Chevy Volt
1999 Ford F150