He's quite obviously not worth 50m even in this climate like, and that's not a detraction from his talent either, it's just a fairly obvious, inflated price. I wouldn't say it's about right for him considering it's now made him the most expensive defender in the world and, as he's obviously not the best right back, let alone the best defender in the world, people are going to use that as the yardstick to measure him by.
And that yardstick is unfortuanate for him. He has two things going against him. The English premium and the Premier League money. Hopefully these are taken into consideration when he's performing poorly. Obviously they wont but they should.