I was going to mention the tyre sizes in the brochure too, but personally I'd go for something like 15" rims and tyres that are even narrower like 175, for better grip in the snow.
Ahh lol come up here where I work was about 7 inch deep and where I live is 3-4inch atm but all frozen! Was wondering because I was told that winter tyres cause more traction for dry roads too so mpg goes down or is that only some tyres?
I wouldn't be surprised if MPG goes down a bit, just because the winter tyres will stay soft at colder temperatures and will have more grip, and more rolling resistance too. But it probably wouldn't be a noticeable drop in MPG.