Sullinger does not seem like much of an upgrade over Millsap to me. In fact, I think that Sullie is Millsap with a serious concern about weight his entire career.
Harsh I know.
Would be a concern his freshman year, but he made significant physical improvement, at least from an eye test, his sophomore year.
Like I said, I wouldn't draft him because he is redundant to Kanter, but I think he will be a steal if he drops past 8.