I just read that both L and R need to be used in this game and they do different things (fire different weapons or something) and because of that you can't really use the stylus, you need to use the thumb strap. I
hate the thumb strap so if i'm forced to use it I don't think i'll get this game.
But then again the stylus gets really tiring after only 10 minutes of playing, I think I might try and practice using the thumb strap again... even though I hate it.

This is why I prefer games like Wario Ware Touched, I can put the DS down on a desk and poke away comfortably.