I don't possess much experience with the mainstream Pokémon games, so I will give you the best answer I can for no bother.
I prefer Drifblim, although I do use a max level fully EV/IV trained Sp. Atk. Dusknoir. But instead of listing the pros of Drifblim, I'll list the cons of Dusknoir.
The Dusknoir I run holds a Focus Sash, but I did consider giving it Scope Lens or Leftovers since I used to do that.
Shadow Ball, Dark Pulse, Ice Beam, Psych Up. In some games this is not possible, but excuse Gen. 1, 2 and 3 for Dusknoir wasn't a thing. Problem is that Dusknoir is frail and probably will waste the Focus Sash in three turns or less. You really just have STAB Shadow Ball while Drifblim gets access to Acrobatics as well. I only sprinkled Psych Up there since I encountered this Spiritomb who had Rest + Sleep Talk + Snarl + Calm Mind. Each time it used Sleep Talk while using Rest it would always go for Calm Mind, then when it's maxed it'll go for Snarl and take the advantage. It does a load of damage, especially on an unprepared Dusknoir. So I keep a Focus Sash + Psych Up ready when I face that nonsense.
Dusknoir also has a smaller base of coverage, while Drifblim gets wide access like it only steals children to find TM access cards. I did my best to perform coverage with the best I had. I did have Rock Smash, but I replaced it for Psych Up just in case, and I was also worried of Cynthia's Spiritomb.
As for Drifblim, I provided you with the best boggling move set that will probably help you. I don't count abilities since I don't really care much of Flare Boost this and Flare Boost that. I also don't count items because of Acrobatics.
Acrobatics - Because of double power with no held item, Drifblim gets STAB and with the decent power it has it gets about 150 damage for each turn with Drifblim - Same base damage for Hyper Beam and Giga Impact.
Destiny Bond - Strange finding Destiny Bond here? I checked the page for the best Drifblim set and so far no Destiny Bond. This tanky and bulky hot air balloon is basically Pokémon's The Great Wall of China. But because of that, you can live some turns to tell the tales with Destiny Bond. Yes, Destiny Bond. Surely it'll be annoying if they suddenly Hex you when you're under their Toxic spell then you're able to faint revenge with Destiny Bond them...
Minimize - The root of all evil. Not only is Clefable capable of this, but so does Drifblim! What better way to annoy the opponent than with a good ol' evasion party?! Best bet is to set up for 5 turns with Minimize for the best results. Things will get REAL ugly when you can become invisible and strike with a good ol' boomfest.
Thunderbolt - A goodie just in case you gotta get the wedgie open. If you deal with other Flying Types, or a Water Type that gives PokéCancer, just remember cut the shortcut with Thunderbolt.
So there it is, all my reasoning for a preferation of Drifblim. I hope you find it useful. Not only for this needy user, but for all of you. I hope you guys get the nerve.
