I do not agree with your assessment of Franklin being C Williams. In fact I see them as exact opposites. Franklin's strength is not his feet or his athletic ability it is his size and physical play.
http://www.youtube.com/watch?v=QLXxk9cUtqA
The Bears have taken risks on low character guys at the position like Tommie Harris and Tank Johnson. I think that Austin's talent is worth the risk and a team desperate for someone with his skills will work with the off field issues.
1[29] and 4[128] 688 points.
2[50] and 2[61] 692 points.
http://www.draftcountdown.com/features/Value-Chart.php