Dude I like in or around the STL area. I havent driven the 370 in snow yet but I had a 350Z before and i just kept all weather tires on it. and i never had a problem. With the VDC system in the car it never slid as long as i drove normal and wasnt trying to crash.
Now the 370 I plan on getting a dedicated set of winter wheels and tires. I also have the option of driving a family suburban if needs be so i think it comes down to how much snow you get. Yeah if there is like 6in on the ground i would leave the Z at home. otherwise get some winter tires or at least some all seasons with light snow rating and go for it. Just make sure you wash the car good especially the underbody afterward to get rid of all the salt and whatever else they put on the roads.
oh and in case you havent see it,this is worth a good top gear laugh and it includes snow.