I have a 2002 325Xi and my dad has a 325Xi Sport Wagon. Both are absolutely great cars and handle very well on snow and ice. Handling feels very similar to the 325i except when in snow and ice and then you can notice a difference when you're not stuck.
I would highly recommend the Xi models if you're going to be in a place where it snows a good amount or if you have a long commute over roads that are somewhat questionably maintained in the winter.
One thing I would have done is get a manual transmission instead of the automatic. It's probably perceived in difference - but I think having the manual gives you a bit more control over the car and the ride - especially in snowy weather.
Hope this helps!
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