I choose all my systems based off the games it has. There's really no point in going for anything else... if you buy a system that lacks games you like, it's a waste of money.

I've had the pleasure of playing both systems, and as systems go they're both wonderful. So I cant help much there. I recommend getting a list of current and future releases of both systems and choosing from that list. Though I will say that Wario Ware Touched for the DS is EXTREMELY fun.