I am not sure if I would need an AT setup binding on either ski (may be just in case if want to walk away from the resort lift), but this is totally unnessesary and could be as an option.
However, I am debating between these 2 "powder" skis for myself, both seems to be good choices....
I believe that price vice Rossi could be a better choice (been a big manufacturer, I probably could find a better price on Rossi vs Moment).
But at this point, the snow is suck! I had visit Northstar CA yesterday and could not find any snow... So, I probably postpone my "powder" ski searching for a while and rent meanwhile if needed (weather forecast shows no snow next 15 days in California Tahoe region, and so far we have 8-18")