If you are going to be anywhere near snow, you want dedicated snow tires. All-seasons are a complete waste of money in my opinion for a Boxster, they aren't very good in the summer or the winter and can be unsafe on snow. If you are concerned with the difficulty of switching your tires, get another set of rims to put your second set of tires on then you can swap them out yourself each season. Also, there is no reason to buy or get snow tires mounted at your dealer, any tire shop can do it, for significantly less.
