My only concern about Bernard, from the way I've seen him play, is just that - that he can get trucked - maybe not just by OLmen, but by physical RBs and TEs.
I would have liked to see him come in with a more muscular build, but maybe he did get stronger and it just didn't show up as bulk.
The other thing that really struck me yesterday watching the Browns at Steelers game, is how the Steelers defenders often seemed to be on their own, to tackle or not. The Bills defense seems to do a much better job of "flowing to the ball" and assisting each other, so maybe that can compensate. We'll see when we play a team with a top TE.