From a personal point of view, I'd be disappointed at letting Sharp go. I really like him. But putting bias and personal feelings to one side, I'm not sure he'd have had too much of an impact this season.
If he were to stay, I doubt he'd start many PL matches at all (especially not with the new formation), and regardless of whether he's starting or coming on as a sub, I don't think he'd do too much outside of the penalty box in this league. And unless we're into the last 15 mins and in desperate need of a goal, I don't think we're in the position to be able to carry someone in the side whose impact is limited to in and around the six yard box (staying up will be hard enough with 11 players, let alone effectively 10).
But still, I'd be disappointed.
And whilst I type, it's confirmed.