Replying to Whistler/Blackcomb in the summer

Hey, me and some friends are thinking about taking a road trip up to whistler sometime in the next few months. Planning on riding the park as part of the 'general public' (not enough dough for a camp, bleh). Anyway, I was wondering if any of ya'll who know the place could tell me when the best time to come up is. Like, should we try and rush it and get there before June 8th so we can hit the whistler park while it's still open, or should we wait until later and just ride Blackstone? Or does it suck in the summer and we should save our dough for some real snow? Any help would be appreciated...