The Manga is definately better, mostly because the Anime skipped the final (and best), third arc. Also, I notice the drawings are generally done better in the Manga.

Anyways, I believe Rurouni Kenshin to be one of the best anime/manga series currently out there. If you like this, I'd recommend Blade Of The Immortal (another excellent manga series), and Ninja Scroll (an Anime film with gorgeous visuals).