Quote Originally Posted by Augury
Some issues that emerge from almost every long-running shounen series is the presence of filler material and clichés that may be a turn-off as you progress throughout the show. If these don't bother you then there really aren't any other major drawbacks to One Piece.
Heheee, that's when you start scrambling for the manga

But just to add/emphasize what Augury said, the drawing style does take a bit of getting used to. I think I had to go maybe 20-30 eps in before I really started getting addicted to it. It's a commitment, sure, but well worth it since the storyline and character development strengthen as the series goes on.