In my experience at sugarbush, while not entirely random, it's difficult to predict the outcome of a particular upslope event or period at any of the mountains you mentioned. Surely Sugarbush averages less than the other mountains over the course of a season, but that doesnt mean that if Stowe gets 12", SB would get 6". I've seen SB get a foot when Stowe got 2". Beyond my understanding how or why this occurs. In my totally unscientific observation, SB does better when the wind is westerly as opposed to northwest, but I may be totally wrong about that.