Well, I just started to play this game. So far I'm enjoying it. Enjoyed the first as well. However, there doesn't seem to be offscreen play which is a disappointment.
There is some slowdown as people have said and the controllers seem to take a slight hit at times because of it.
My biggest complaint/question is what the heck is going on with the sound mix in this game? Music and some special FX come out the front speakers while any voice is pumped out of my surrounds? I'm running this game through any Onkyo 818 that I've never had any issues with. I think the mix is super off. For reference I bought the game on the Eshop. Perhaps the retail copy is different? It just seems really off.