It seems some of you haven't read the thread you're posting in. Please do so, and you'll find some reasonable argument on Ono's merits, its flaws, and why you'd want to use it over Salamence, Garchomp, or Dragonite. It also contains a few good set ideas for Ononokusu.
Butterfly Dance passing is a terrible idea. If you would read the other posts below where the original poster suggested Butterfly Dance passing, you would receive a thorough explanation of why it's so bad. Fluffy Otters also made a good argument, and suggested Blaziken as a Baton Passer, which is a great idea, considering Ono's Dragon typing allows it to switch in on a move that would threaten Blaziken.
One thing I want people to note; I've said it before and I'll say it again. Ono's SD set is not walled by Skarmory. 2HKOed=/=effectively walled and is in fact the opposite. It can then proceed to wreck the rest of the opponent's team. DD sets, especially semi-bulky ones, can find themselves in a pinch against Skarmory, but SD sets do not.
Choice Band sets are a great idea, and are in fact listed on reyscarface's unofficial analysis for Ononokusu (
here). Although Dragon Tail seems like a good idea, Ono lacks the bulk needed to use it effectively. An example of good users of Dragon Tail would be Gyarados, a pokemon that can easily take a hit and hit hard back while phazing out.
As for the prevalence of Ononokusu in relation to the other dragons on simulators, of course Ono will see little use in the beginning. With monsters like Garchomp unbanned, of course no one will want to use something as relatively unthreatening as Ononokusu. Once the metagame has developed and the broken pokemon banned (Chomp and Mence might not necessarily be banned), Ononokusu will begin to be used as it's meant to be used: as a bone-crushingly powerful wallbreaker, or an incredibly strong Choice Bander, or whatever uses anyone else might find for him. I've found some decent success using Ononokusu on PO, although I've only used the SD sets so far. If you don't immediately write Ono off as a bad pokemon because of its lower speed and defenses in relation to the other dragons, you'll begin to see its usefulness and appreciate it for its merits, namely its huge attack. Although Ono can't sweep as easily, it can attack with much more force than comparable dragons.