It's funny, I used to think of Chicago as a car town...until I lived in Dallas.
seriously, in that city, you see some of the great stables like you have - that's quite the garage.
But the heat in Dallas is...hard to deal with. I would say that you probably won't use the drop that much on your M4 if you went that way. It's just too damn hot most of the year.
M2 might be a better choice (amongst other reasons, like cost, rarity, etc.). Just my $.02.