Cold weather riding has its points. For one thing, people think you are crazy and give you a bit extra room! Up to three years ago I would ride in nearly any weather including a 50 mile round trip commute in sub-freezing weather.
On the air cooled 750 Nighthawk I would just swap gloved hands (throttle lock) down on the cylinder heads for warmth. The Pacific Coast would never develope enough heat to do any good from the radiator exaust so on the coldest nights (mid-20s) would require a hot tea stop about halfway home.
This is not the time to cut corners, you need well fitting, confortable, gear that will keep moisture out and heat in. It should be adjustable to allow ventalation and removal of excess heat. Gor-tex and Thinsulate type materials are available from many sources, I get most of my gear at the end-of-season-sales from Cabela's as I have delt with them for years and know their quality and sizing.
If you have a GOOD recreational producs store go there and try on the products unless you really know what you are getting from a mail order place. If your bike shop is a four season dealer (not here in Florida) you should be able to get snowmobile gloves and suits at sometime inflated prices.
Style or not, this is the time to worry about protection over looks. Even if you like the spority look of the short screens the larger coverage replacements can save a long, cold ride. Due to the sensitivity of the Spyder to voltage and current drains in the computers I would be very careful about electrical heated gear. Check with your trustworthy maintenence person and only use the approved on-board outlet, don't just wire in some convienent spot.