I'd take Day in the 2nd round. I believe that in every draft you have to take at least one "risk". Take a shot in one round on a player who is a home run potential pick, and that's exactly what Day is. He may never amount to anything more than an AHL defensemen, but there's also the chance that he puts it all together and becomes a legitimate top-pairing defensemen in the NHL.
So many of the great defensemen in this league were not 1st round picks. Shea Weber, Duncan Keith, P.K. Subban, Kris Letang, Dustin Byfuglien, John Klingberg, Mark Giordano, T.J. Brodie, Andrei Markov, Tyson Barrie, Justin Faulk, Sami Vatanen, Marc-Edouard Vlasic, the list goes on and on.
If he's there in the 2nd round, take a shot.