Sports Illustrated recently rated Matthew Stafford as the 10th-best quarterback in the NFL. To me, it's a moot point at this stage of Stafford's career to rank him anywhere.
He just hasn't played long enough to get a line on exactly how good he actually is. He has certainly proven he has the ability to some day time rank in the Top 5, right up there with Tom Brady, Drew Brees, Aaron Rodgers and Ben Roethlisberger, but any such assumptions are preposterous are at this time.
What exactly has Stafford won? Nothing. The Lions are 6-2 and developing into perhaps a championship-caliber team. But they are a million miles away from that right now.
The pressure hasn't really been on Stafford yet. We don't know how he is going to react to it. The Lions have yet, in reality, to play a truly meaningful game with Stafford under center. Those will likely arrive, for the first time in Stafford's NFL career, the second half of this season.
Until then, it would be inaccurate to even say "The jury is still out on Matthew Stafford."
It's more like the evidence is just starting to be presented.