I liked that he came across as passionate about playing for his country. A little ott sometimes but in the England squads he was involved with, we often showed almost zero passion or desire. He has had some good seasons, although most of these were with world class defenders in front of him.
I don't think he is a terrible keeper, but I do think his best performances are behind him. Mentally, I think he's struggling to perform not being a part of a top team, as he is no longer competing with the very best in the world (a small pool of GK's). The focus that would have been on him when he was England number one and performing in the Champions league would have kicked his arse every single day as a relatively young keeper, trying to be the world's best and hanging in the elite.
Now he still gets paid a lot of money and sits in that much larger pool of decent to good keepers where he is competing with hundreds of others-many still hungry to represent at international level for the first time, or secure a move to a big club/win a big contract. Irrespective of what he thinks or says, that will have punched his motivation directly in the Travellers. He could absolutely represent a decent PL side with the right attitude, I just dont think he will ever be in a position to do so, and will not even be talked about in a seasons time.
He should go to a club where he will play every week, but I doubt he will ever get back where he thinks he belongs.