One Piece's art style has always rubbed me the wrong way a bit. I'm not claiming it's bad, since I know it isn't, it's just not my favorite/something that appeals to my taste. Some of the scenes in it actually look pretty awesome though.

As for my favorites...

Takeshi Obata's style is one I like, though towards the end of Death Note it started to descrease in quality.

Tite Kubo's looks great, though around the beginning of Bleach it was much more mediocre.

Two other styles I like are CLAMP's and Katsura Hoshino's. CLAMP is great with details and expressions, in my opinion, and their color spreads are gorgeous. Hoshino (who does D.Gray-man) has something about hers that's just nice to see, though there's times when you can't tell what's going on because she's tried to fit too much into one panel.

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