If it were me I would just use the stock wheelset you have. Winter cycling is different than summer cycling- with the extra clothing layers, wider tires, and muck on the road you are never going to feel like you are flying the same way you do on your summer bike. To invest $1000 on a set of wheels that will be ridden only on wet, salty roads only with winter tires seems a bit of a waste.

Consider your winter rides training for your summer rides. You'll feel really fast when you get back onto your other bike for the first time.