My Dunlop SP5000's have been an excellent tire (even lasted though a 70mph pothole impact w/out damage) but my tread is growing thin and I'm thinking winter conditions might be a little heavier than last year so I'm hoping to jump up to a tire that's as good in dry as it is in snow. I've heard Nokian over and over again as a solution to this request. I'm sold on Nokian's but I'm hoping someone here has experience with either the NRW or WR line (or both). I am hoping to find out which one is better at lower elevation snow driving and icy conditions. Any info appreciated. Thx!

...and my car is rear wheel drive :) I think they handle well on dry but switch in the summer to the Zs.

You can get Nokians in Denver at Meadowcreek Tire just north of I-70 on Colorado.