I'd rather get Mettenberger or Murray later, or Fales, Smith, Garoppolo, yeah probably 5 dudes before McCarron. Is the NIU guy coming out too? Jordan Lynch? If so then him too. All of these cats could probably be had in the 3rd or later.
Mettenberger has a cannon and can find space in the pocket. I'd be completely fine with him in the later rounds. The others you mention also trump McCarron.