You take Mark Barron every day - huge gap between him and the rest. But if, as likely, he's not available to us, my second vote would go to Alfonso Dennard. Might not be good enough as a boundary corner, but I love his feistiness, is perfectly good enough to play coverage in the safety slot and is a good tackler and at #48 is really good value. I like Harrison Smith but there's not enough there to justify the high second round position he'll likely go - just doesn't impact plays enough and is too soft a tackler.
Stay away from Markelle Martin - there's a reason he's got a third round grade, he's not good enough. fine as a double dip, but not our number one safety taken in the draft.
Exit question - If Kirkpatrick falls into the 20's, do you trade up for him. Could be a quality FS in the NFL.