If you live a snowy climate dont get all seasons, just try and avoid all seasons period...
best way to do it is keep a set of rims with summer tires mounted, and a set of rims with snow tires mounted. ( I even go as far as getting my alignment checked each time i switch, just in case, and to maximize tire wear)
I can not speak highly enough about having a set of dedicated snow tires for winter
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So it already sounds like u might keep the old rims for winter, then definately get summer tires for your new rims. Then you will have the chance to truly enjoy a set of summer tires.
All seasons are such a huge compromise that they usually cant compare to dedicated seasonal tires.
btw, i like to troll the g35 forum every once in a while. Id like to get one, but I dont really have a NEED for one, since my current car treats me so well and plus i dont have a car payment right now wich is nice