My initial reaction was Arizona because it would be nice to see the franchise get a cornerstone to help them truly establish themselves in that market around a true face of the league type talent.
I didn't vote that way, however.... If the kid is the real deal, would prefer he stay out of the flames division/conference.
Next best would be buffalo (which is how i voted). That team has so much youth/talent coming down the pipe, could be an awesome team to watch. More importantly, living in TO, I would get to watch him enough, and it would be frigin sweet having the Leafs have to deal with McDavid in-division for the next decade or so