You're a lefty too? I can't stand any FPS on the DS because of it. The face buttons do not compare to an actual D-pad and my thumb gets quickly irritated.
So Dementium, Moon and Prime Hunters are all a no go for me.
Maybe that's why I never liked them either. I've honestly never found it to be that noticeable of a problem, but maybe it's just a little bit off that it makes it unenjoyable.
Being a lefty is rough in this Wii/DS world. Art Style Base 10 is made for right-handers only, and there's a handful of Wii game (No More Heroes comes to mind) that force you to either play the game backwards, or play with the Wii Remote in your right hand instead of your left.
I do enjoy the confused looks I get from people showing off games at events when I move the Wii Remote to my left hand. "No, put it in your righ-" "I'm a lefty." "Oh, ok."