The best injury for an NFL draft prospect is the one that can be forgotten and never spoken of again.
That's the kind of injury that doesn't derail development when a prospect knows his new NFL team. It also doesn't keep him from contributing immediately. And most importantly, it doesn't napalm his draft stock and cost the prospect money after plummeting a round or more.
Most of the injuries of note among the draft's top prospects fall under that category, and they can either be cast aside entirely or come with moderate concern at worst.