If you're going to get dedicated winter tires I suggest you get 17" or 18" rims. I had Pirelli Ice and Snows on 18" rims on my 2005 and they were great (255 all around).
Not sure what is available for the E70. You are fine driving on winter tires from TX to CO. It won't hurt them.
I don't have any experience with the Lattitudes. Either do a search or someone will be around to answer.
Good luck and welcome
