Native Instruments Bandstand -- any experience?

I'm considering getting either some kind of controller or just Native Instruments Bandstand. I like the simple setup of this program. Does anyone have any experience with it?

Is it possible to play it with a computer keyboard or is it possible to mark the notes/chords you are playing by clicking on the on-screen keyboard? Is it compatible with Vista or does it work well with Vista?

I've considered getting an Edirol PCR controller, but I want really simple gear.

But what if you play chords on a piano, can you play more than one key on the midi keyboard at a time?

I'm getting Native Instruments Bandstand. Thanks for the help!