Most products like N-F, should hold up better during the winter months than during the summer months. It's the cold that helps bond the product to the paint. It's the ((HOT)) temps and the ))SUN(( that destroy the protection of the product on painted surfaces.
Then again, how will the vehicle be cared for during the winter months? Strong detergent car washes will slowly remove the protedction from the surface.
Nu-Finish should hold up quite well although any extra quick detail type product after washing will help during the winter months as each case and vehicle will be different.
In the past when I only waxed my vehicle several times a year (and just prior to winter as well), the paint shine didn't hold up as long over the years as using a just quick detail type product after "EACH" wash. And it doesn't take much time/effort to mist a whole vehicle after washing.
I keep my vehicles into their teens(15-18 yrs) and thus far, by using only quick detail type products/wax-as-you-dry type products, even my 10 year old vehicle still shines like new compared to my other vehicles that I have had in the past(using only wax/silicones several times/year). And I'm making the ~10 year comparison between vehicles.
Today, I would rather quick mist my vehicles after each wash, than to wax/remove 4-5 times/year(with weekely washing/drying ONLY between waxes).
Yes, I do keep some wax/silicone products around and have recently tried and given my reviews on...Eagle One Gel Wax(E1GW)