I would say.... can three consistently, CAN do 5's but... can 270 out one way consistently, maybe the other way sometimes. and 2-7s onto flat boxes. Then of course there are the outliers that are much worse or much better, but i think thats a good average.
As far as real skiing, powder and such, I think an NSer on average will be a lot better than most, or else REALLY bad at skiing powder.