>is it worth the time and effort to get up there for a few days or should we just stay in Vancouver for four nights?

I would say stay in Vancouver, although you could certainly get the sense of Whistler in less than a few days. A lot of us locals do it as a day trip.

Keep in mind there are mountains 30 minutes from Vancouver - Although not as impressive as Whistler, a the gondola ride up Grouse or a hike in Cypress Provincial park will certainly put you deep in the mountains and still give you lots of time to see other stuff.

Cheers,
Geoff Glave
Vancouver, Canada