This is a preorder for the new pikachu controller. Hori are highly rated (compared to the PDP controllers) which are one of the best ways to play smash. The deal gained heat for a similar price (without delivery) when preordering from playasia but this is from Amazon which will be faster and will avoid potential customs charges.
This controller plugs into the wii remote, acting like a classic controller but with the ergonomics of a gamecube controller.
The one main difference between the gamecube controller and this is that the L and R shoulder buttons are digital rather than analogue. Classic controllers don't allow for analogue. They will activate faster but, if gamecube games are released for the Wii U in the future or you are otherwise able to get them to play, things like fludd on Super Mario Sunshine won't work as well. This is because fludd responds to how hard you press.