9. He's accurate, hits hard, doesn't waste much, can stop an opponent, and can set up his shots smart while cutting off the ring efficiently. He's not too dynamic in his offense and he often advances throwing the same rhythm of 1-2's and 2-3's, and he's not one to set up knockouts consistently and spectacularly, so he's not a ten. But he's great.
I give him an 8. PBF is a very good offensive fighter at the championship level. But his style over the last few years has shown less of it. In his old fights at lighter weights he was much more entertaining.
He's hit 10 on a couple of occasions, imo; most notably against Gatti and Corrales. But I haven't seen a display as impressive as though in recent years. As Bogotazo stated, he tends to limit his offensive rhythm to single punches or one-twos these days, and doesn't vary the plane of his attack from body to head as much as he used to. Still, his punches are extremely accurate, and hard enough to keep fighters in check, if not stop them entirely. So, I figured an 8 was a decent rating for him, taking all this into account.