I have him at Portsmouth and I'm just entering 2012/2013 season and I've had since 2008. The first three seasons he didn't really hold down a place in the starting 11, but I used him a lot from the bench by the end of the 2nd season.
But by the end of the third season he had just abount cemented the AMC position as his own and he has been pretty good for me since. On his good days he can dribble he ball round anyone and can put some superb passes through the oppositions defence. However he can be a little inconsistent at times. But then again he doesn't seem out of his depth with my team who have just won the champions cup and he is now a regualar starter in the French National team.
So I say hes worth keeping hold of, try putting him on loan if you can spare him so he gets some first team football.