I can't agree that the animation sucks at all.
The first contact I had with One Piece was with the manga. I have all the books up to the Skypiea arc but stopped there and about a year later I picked up the anime instead, the books are quite expensive and I don't want to read them online
Oh, and the Japanese voiceacting creates the whole atmosphere imho
The only thing I hate when reading the Manga is that I miss their voices