I can't imagine James Posey not opting out. He wanted a long term contract last summer but couldn't get it. He's shown his value to the entire NBA once more and he's gotten a huge amount of appreciation that will likely only increase as this playoff run goes forward. I think he's got a great chance of getting the full or close to the full mid level exception. There's several teams where he'd be a great signing for including a bunch of contenders like San Antonio, Houston, Cleveland, Orlando, Detroit. I think all of those teams will be active in looking to spend their midlevel this summer. A bunch of others too that could make Posey good offers.
I'd have no problems paying Posey for 3-4 years. It's the 5-6 year midlevel contracts I want to avoid. 3-4 years is fine, this group will still be together at that stage.