The size increase of the 3DS is unessesary, it's more likely to break, it's more expensive.
I'd personally recommend the regular 3DS any day
edit: the size increase makes regular DS games look blurry
Unless you're a toddler or a very short midget, that viciousness you see in dogs very quickly turns into intimidation for cats.
Even then, you have to be agitating it a lot to provoke them