No question, Luck.
Nobody enjoys watching RW3 play his game more than me. Glad he's a seahawk with the "too-short" chip on his shoulder. Heck of of a cerebral athlete with athleticism to spare. Couple that with an arm and a knack for the game that out-weighs his size. Add the maturity and classiness and fans got something to be proud of.
Luck has all the cerebral/maturity/athletic stuff. Has the size/arm. More vision whether on the run or in the pocket. He can run and scramble, but also has that Rothlesburger-like ability to make throws with defenders draped on him unlike RW. And like said earlier, all 32 GM's would take Luck over RW3. Both are poised under pressure and can bring it when their team is behind late in the game. But physically, Luck is without a doubt the most desirable young NFL QB.
A fair comparison would be Kaep vs. RW3. Kaep, superior athleticism, arm, speed. Inferior maturity/classiness. Doesn't show the cerebral part that other top flight QB's in the league do including RW. When Kaep looses he losses big, unlike RW. If RW was playing behind the likes of Satley, Ipuati, etc.., with any of the weapons of either the 9ers or Hawks, wilson would kill it. Taken, Kaep hasn't had the offensive skill position arsenal so far this year, but he's had an intact O-line. RW's team has one loss, on the road, to a very good Indy team. Same Indy team mauled Kaep on his team's home field.
RW so far is without a doubt the more "wantable QB" over CK, especially with the too-short/underdog factor, from a fan standpoint. But Luck is the most desirable young NFL QB moving forward with all the upside including the unteachable vision from the pocket (height). Only stats that matter are wins and points. Luck joined a 2-14 team and took them to the playoffs as a rookie where as RW joined a talented team on the cusp that needed an upgrade at the position. Again, so far in '13 Luck has led a very decisive win on the road against the vaunted 9ers, and made the plays to beat the hawks at home. (some would say that the 9ers as a team have maxed/regressed as a team going to kaep over smith). By virtue of head-to-head, Luck beats RW, and obviously Kaep (and RW destroys Kaep X2

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10 years from now Luck will still have that vision/height and ability to make throws with defenders around his ankles. RW will be struggling to find throwing lanes. Both will be making plays with their feet. If both have similar mediocre players on offense at that time Luck will be more successful.