Right now, I don't think that de Gea is having his best years with the team. I think his performance peaked much before than now. However I can confidently say that I'm pretty contented with his performance in the recent years. His reflexes are still in a solid condition and we have seen some good examples with some critical saves of him so far also.
Courtois can literally be the best goalkeeper among the ones who are actively playing football. He was really impressive against Manchester City also despite that big loss. Apart from that, I think that Neuer's best version is better than de Gea's. Neuer is rather a "sweeper keeper" and he has done a great work about that so far.
No doubt that Neuer has revolutionized the keepers' game and yes the term sweeper keeper applies to him. I am not sure but isn't it that it exists because of him?
In terms of de Gea, the problem is not about his reflexes. He is still quick to react and yes he can still do critical saves. But what I noticed over the last couple of years is that he also more and more makes critical mistakes. I don't know whether my perception here is off or whether you share that idea as well, but in some situations during the game he creates unnecessary dangerous situations by keeping the ball for too long and waiting until the opponent already blocked all passing options. I don't like that type of game really.
