We should not hesitate to go grab this kid. Lewis and Greer are both great examples of players who took a few years to develop into good CBs. Milliner has as much talent as any CB in the league just hasn't tapped into yet which is very likely he never does. He is just entering his prime at 25 and with the right coaching along with some luck in the injury department the kid still has a chance to be a special player. I think injuries are a huge factor in why he has never fully developed always setting him back. At this point it can't hurt one bit to bring him in and we have two very good DB coaches in Allen and Glenn to get the best out of him.
The last thing we need is to bring in more people who are guaranteed to get Injured. Especially when we are already paying players to just sit on the sidelines. It'd be different if he got injured once maybe twice but it's been a recurring problem and frankly with our Injury luck it will surely happen again.
Low risk, high reward. He comes at the price of a 1st round base salary but IIRC, the Jets didn't exercise his 5th year option so he'd get a chance to prove himself this yr and possibly get an extension.