I agree he is a great qb. Best ever is tough to say about any qb. I personally think Marino was the best, but he never won a super bowl. I also think Stabler was one of the best ever, but he only won one super bowl. Montana has a bunch of rings, as do Bradshaw and Aikman. Big Ben has two. I think Stabler and Marino were better than any of them. That's what makes opinions great, that's just what they are, opinions.
Other players can make qb's look great, or bad. For one year, Jim McMahon looked like the best.
Currently, there are some very good quarterbacks, with Brees, Manning and Brady being probably the best of the bunch (with McNabb, Schaub, Romo and Rivers being in the next group).