ff4 for the ds is very good. it adds enough to be a different experience from the other versions. full voice acting for a bunch of moments in the story, a new ability system which let characters gain new abilities, including a few from bosses, a new summon was added in the ds version only, you can set up a rudimentary autobattle system to help with grinding a bit, there's 2 hidden super bosses stronger than the final one, namingway has his on sidequest that spans the entire game, and you can replay the same files 3 times to set up 2 characters with the break damage limit ability to help with the super bosses.