I'm not sure where I read it but someone did post some months ago (2-4) that stats show that "Good teams don't use Dragnoite, they avoid Stealth Rock weakness". And I agree with this. Just think, THINK, if you're unfortunate and the Rocks are up, you are basically running only 5 Pokemon in your team. Dragonite is absolute crap if Rocks are up. While Salamance would still be quite fast and be able to outspeed a good amount of the tier and will put a dent to at least one thing.
But yeah, on the other side, if you're usually/always successful in spinning away, then DNite is the best Dragon.