I’ll pay 1 mana more than for Air Elemental with a trigger like that.
I do worry, though, that this is a bit of a liability. If you’re milling them, you start with a target of 33, more if they mulligan. The earliest you cast this is turn 6, so best case they have 27 cards left. You need to hit them 6 times to win through milling. You have a good chance of knocking a good card into the yard, but a similar chance of making them draw something good 4 turns early. I generally don’t like trying to mill them out with 1 card because if you focus on that too much, you’ll likely end with them at 5 life and 7 cards in the library and they’ll kill you because they focused.
Luckily you don’t have to stop dealing them damage because this mills by hitting them, so I hate it less.
Also, I CAN read, thank you. It says “Target player” which means you can totally mill yourself. This lets you delve. This could be a useful case for this card. All in all, this is a fine flier and you likely play it. Just be careful – this card’s trigger isn’t as straightforward as the other dragons’ and this will require some planning.