I don't know why people call him overrated. Just look at the numbers, he is clearly the best young player in Europe. The 20 year old Cristiano Ronaldo was just like him.
There are dozens of players that are better than Willy in attack. Mata and De Bruyne are clearly better attackers, but Mourinho prefers hard workers with three lungs.
Why not? He is turning 30 soon, Chelsea might be his last chance to play for a European top club. He has only played 8 Champions League matches, he probably wants to prove his class. He can definetly earn buckets of money in Qatar/US/Australia/whatever.
If true: good luck for Atleti to buy him back, it won't be cheap. One week ago he didn't look that unhappy. Also, he wouldn't have a chance to win anything at Atleti, why would he go back?
I wouldn't pay 32 million pounds for Benteke even if we didn't have any strikers. He is a good player, but I think he is like Rémy. He is okay, scores a couple of goals but not outstanding, not a world class player.