I think Fusitua has improved even more since his initial stint in first grade. The amount of improvement has been compelling. His form says to me he wants to own his spot. But more importantly Hurrell's injuries have slowed his growth.
His impact versus mistakes balance hasn't been good. I'm not saying he's not good enough. It's that, at some point you have to evaluate whether Hurrell's potential for destruction yet lapses in defence are worth waiting for when injured so much. He takes a while to recover and if he has a weight blowout as well we might only see him half a season.
Whereas Fusitua looks rock solid in defence and his attack has gone to another level again (last year I was doubting his pace but he's shown that with injuries aside he is very quick).
On form Fusitua gets the nod IMO.