Eh..."amazing" is pushing it. "Functional" would be the word I would use for it.
To start, I don't care for Heroes of the Storm. Despite playing carry-type heroes, I never felt like I could actually carry a game like I could in League of Legends. Blizzard is working under the mistaken assumption that a random group of five people is capable of working together to take objectives, so they made that aspect of the game their focus...and it suffers for it. It is much, much harder for one person to win the game by themselves, and I never felt as powerful in this game as I did in League or DotA. Also, I'm not sure why mounts exist when the bonus movement speed they grant is only a small step above walking.
But it was the pricing structure that made me leave. I already give Blizzard $15 a month for WoW, and several times that for booster packs in Hearthstone. They don't need to make their MOBA this expensive, because the game isn't that great to begin with. I expected way better than this from Blizzard when they decided to throw their hat in the MOBA ring, but if they go into this fight thinking they start off equal with the already established powerhouses (by pricing their items worse than their competitors), they are sadly mistaken.