I'm getting a PS Vita for Christmas to get F and F 2nd. The problem is, which should I get first? F seems easier to adapt to, but F 2nd has cool double stars, linked stars, etc.
For me, my top priority when purchasing rhythm games is the music. If there isn't a lot of music in the game I like, I won't purchase it. Note that there are easy levels on both games. if I were you, I'd probably pick the game that has more of the music I like.