Got my 2014 in January and it handled the winter fine. I tend not to use a lot of heat in any vehicle so with the heated seats I lost range but not massively like people who run the heat non-stop. Also my Leaf is garaged and on L2 so preheating makes a big difference. I did a couple 100km days and got down to LBW a couple times in the really cold temps. Now with the nicer weather I am seeing 150km plus with the range. I did one 190km day when I helped out with a road bike race and was the wheel car in z couple races. Most of the driving that day was 40-60km/h so it was easy to get the extra range.
As for driving in the snow I left the stock tires and it was fine. I am only leasing so I didn't want to get winters unless I absolutely had to. I found the car predictable in the snow so I am going to stick with the all seasons for now. I drove a loaner Versa in the snow on the stock all seasons and it was absolutely horrible compared to the Leaf.