In Computer Cowboy's rankings of the Online, the Bills are 26th in the NFL but this is almost entirely due to Brown...
Dawkins is a 91% and the rest of the line is pretty solidly graded and then Brown is at 8%. Basically he alone takes them from a top 10 ranked line according to his metrics to 26th.
That says a lot and none of it is good. Better hope most of his issues were back related last year and he has a clean bill of health this year.