Gracie will win in the battle of hands, unless Storley shows something he's never shown before (I'd absolutely not hold my breathe).
Storley could get caught by something on the ground, I wouldn't necessarily expect him to get caught by something though, I think the balance of offense/defense in BJJ right now heavily favors defense. But Storley isn't really a fanstastic finisher on the ground either and I'd be all the more shocked it he was able to maintain position on the ground long enough to do so vs. Gracie. Personally, I'd be down for this fight but it might be just a lot of transitions on the ground. Which I would like, some others might not.