I was thinking about getting a KP2 sometime in the future.. would that do for the bass?

Or would i be better of paying out more at first and getting an EMX..

Ill be using it with headphones for just playing, but ive got a guitar amp.. and my Hi fi is reletivly good.

Ive got a decent home PC, and was planning on downloading the thing from KORGs website.

If the KP2 wouldnt do the drums, what would be a cheap (but okay) start for the drums?