Depends on two things really.
First, is he coming on a free? If yes, then definitely we can take a punt on him. Even at 30 he will be a productive player especially considering the amount of effort he puts in to keep himself in top shape. Also, he is a thorough professional and won't consider this as his retirement solution and last paycheck. To add to the fact that fans will take to him almost immediately and will increase our commercial value significantly.
Second, do we already have a young promising player playing in his position? If we have somebody who has the potential to be world class then I wouldn't want to displace him at all because you can't have players like Ronaldo sitting on the bench.