you cant go wrong for 4 seasons passes for 579.
it's more like 6
the epic pass gives you unlimited, unrestricted access (i.e. no blackout dates) at vail, beaver creek, breckenridge, keystone, heavenly and a-basin.
that's the equivalent of just less than 6 one-day tickets at vail for unlimited access to 6 mountains all season. it's an incredible deal.