He may have a plus fastball and a sometimes devastating curveball, but the first thing FSL observers mentioned about Hellickson was his savvy. He could just reach back and blow away a lot of hitters, but he was much happier to keep them off balance.
Hellickson's fastball sits between 92-94 mph and he can add a tick more velocity when he needs to. On the days when he was locating his 12-to-6 curveball, he was almost unhittable, though there are games where he'll lose the feel for it and it becomes a harder 11-to-5 breaker. He also believes in his solid low-80s changeup.
Vero Beach's pitching coach, R.C. Lichtenstein also has a quote about his advanced feel for pitching; e.g. he'll throw a changeup in a fastball count, that kind of stuff. There is certainly a lot to like about Hellickson, and about the only flaw you can find is he doesn't have a very projectable body, so he might already be at his ceiling. Even so, for me, Hellickson profiles as a number 2 or 3 starter down the line.