Both of them put a lot of work in their manga.
Yet, Kishimoto doesnt use those grey tones(he used them in the last chapters, which reminded me of One Piece Manga) that add more effect.
Still, Oda's manga is herder to read. He puts a lot of details in the background and aglomerates the page.
I like both, I read both.
My style of drawing is somewhere between them, but I am not that good at backgrounds and perspectives.