I was seriously considering putting a couple of these in my mono-white Standard deck, but they got pushed out at the last minute. Even if it's just a one-shot, giving a bunch of your attacking creatures flying is really good. Unfortunately it only affects Humans, but if it gave all your attacking creatures flying, it may be a bit too good. It also has to attack to trigger the mass flight which leaves it open to death from combat. Still, this flying horsey is pretty decent.
Pros: Gives attacking Humans flying
Cons: Must attack, only affects Humans