Kids in ski and snowboarding school for three days. Skied and snowboarded as family two days. Grandpa skied four days. Joel snowboarded one day, skied one day. Martha skied two days.
Joel fell often. Marty didn't fall once.
Vail has more ski-able hill, and we're more familiar with Vail.
We ended up liking Beaver Creek's ski school (very organized yet laid-back), the town of Beaver Creek, the ease of getting to the top of the mountain (gondola from Westin, then bus to top), and the Westin.