Depends on the type of snow and terrain and also conditions on what you should wear. When I was going through a pre sniper course in Germany last year we were doing stalks in the snow after a storm but there was still alot of brush on the ground. So you actually didn't want to use alot of white/grey on your ghillie otherwise you would just look like casper walking across a field.
Now for pure snow, I would rather have coveralls with some loose straps of some sort of cloth on it. Ghillie suit is just something to improve your silhouette and the human outline.
Come to a snowboarding forum and I end up talking about sniper shit
. Also the ghillie suit posted above is horrible, the fake nylon shit sucks and puts off too much shine and even after completing a ghillie wash will not dirty up like you want. You want to use real natural jute fibers and then you only want to use about 50% of that on your ghillie suit. You want to use as much natural vegatation as possible, which you will also need to change out every half hour or so depending on how hot the weather is and the terrain. One of the things that we were taught in sniper school is veg up 10 times before taking 1 shot