It's the game that Zelda DS wanted to be.
One of the things about the difficulty is that for me, it is at that perfect difficulty level. I've died a few times, and some fights I'm really worried if I'm going to make it through, but I always seem to be able to proceed.
And I still don't like the whole microphone thing... I live by myself and I still feel foolish yelling into it!
I really like Ninja Gaiden DS, and it does have extremely responsive controls for the touchscreen, and no horrible camera problems.. Still, I think I preferred Zelda DS much more, and I think the controls were at least as well implemented if not better in that one. I am not a big fan of the Ninja Gaiden series but am a big fan of Zelda, so that could have had something to do with it.
My main problem was that the combat was far too easy, and the sailing parts dragged on and on.
I will say the controls and graphics were fantastic, and I had a lot of fun playing this game. But still, 90 percent of the bosses were jokes, which is obscene for a Ninja Gaiden game.
It takes me about three tries to defeat a boss. That's sufficiently difficult for me, at least.