Yuugi. Hands down. Joey's good, but not as good as Yuugi.
Tristan... I don't even know if he's any good. He's hardly ever shown dueling. Who knows, he could be a pro and we'd never know because his character wasn't explored as much.
Honestly, I think Yuugi is just as good of a duelist as Yami. He's not given enough credit. Yami gets almost all of the credit. (Don't worry I still love Yami)
I think Bakura is a good duelist too, even though his Occult Deck has a couple of flaws.
Bakura: Oh please, I'm the best duelist. I'm better than the Pharaoh will ever be.
Me: ...You've never won in a duel against the Pharaoh.
Bakura: I have to!
Me: Oh really? Name one.
Bakura: Um... that one... when I summoned... you know... that uh... that thing.. and the Pharaoh.. summoned a God monster, and uh...
Me: Uh-huh... go on.
Bakura: I... *sighs* you're lucky that I could never send you to the Shadow Realm.
Me: :D Aren't I??
Yugi is better at Duel Monsters.
Rest of the guys: HEY!
Yami: Don't I count?
Bakura: Thats not fair! I'm better at him at Duel Monsters!
Seto: No you're not. Remember, he defeated you a few times.
Bakura: WITH THE PHARAOH'S HELP!!!!!
Me: Quiet you! Sorry for his rudeness, he's always like that.
Me: Thats my final answer. See Ya!
Well.....I THINK THAT KAIBA BEATS 'EM ALL!!!! H-How could you forget Kaiba, Seto!?? And you didn't include other awesome main Duelists like Kujaku, Mai (Mai Valentine), Pegasus J. Crawford (Maxmillion J. Pegasus), and Ishtarl, Mariku (Marik Ishtar)?? Honda, Hiroto (Tristan Taylor) isn't even a duelist, he doesn't compete in any tournaments! By the way, out of those two duelists and (ugh) Hiroto, I think that Katsuya, Jounochie (Joey Wheeler) is better because he has a fair chance in winning. Yugi can consult Atemu (Yami/Atem) whenever he is stuck so in a way it's two against one. Also by Yugi do you mean Atemu of cute little Panda Yugi??
SAYONARA!! =^, . ,^=