As is so often the case in life, there are the "in" places to do and be seen at. For the Toronto snow crowd, that place would be "Blue". As an Intrawest property, it has all of the expected "apres ski" offerings associated with such. As for the hill, it has more vertical than Moonstone, but most of the runs have a "flat" that if the crowd prevents you from carrying enough speed, can be a pain on a snowboard. As it is a weekend resort, the lineups can be bad on a weekend.
Moonstone is almost everything Blue is not. It is family owned and their only goal is to provide as good an experience as their hill can provide. There is no night skiing, good for some, bad for others, but it does ensure that the majority of the hill gets groomed early and then has all night to "set up" Fresh tracks are possible here. I don't do the park, but from the feedback you hear from the kids at the cafeteria during lunch, they rave about it. There are no accommodations on site, but they do provide the essentials on site. Rentals, Ski Shop, Cafeteria, etc. As mentioned above it is closer and an easier drive to get to vs. Blue. On weekends it can be busy, not as busy as Blue, but they do have a great number of high speed lifts.
During the week, both hills are wide open as is the norm in most places. If Moonstone does have a drawback during the week, it is that a large number of schools will do their ski days at Moonstone. If you know where to go, you can avoid the majority of students on the hill.
As you might have guessed, I prefer Moonstone. Very easy day trip, they make a ton of snow and it is ALWAYS well groomed.