This album instantly takes me back to 2003 whenever I hear it, but I don't think it has aged well. It's still stuck in 2003. If you only download "Hey Ya", then you're not missing much from the rest of the album.
OutKast's duo have made a cohesive statement that not only cries at the boundaries of rap music but vaults over them to a place where the music sounds like neon colors and the only rule is that you must free your mind. Your ears will follow.