I know many keyboard players including myself use more than one keyboard or at least two keyboards during gig or live shows. I am thinking about instead of buying another high end second keyboard for top which is oftentimes used for lead, brass, or organ sound while the bottom keyboard is used mainly for Accoustic and electric piano sound. Why not just buy an inexpensive keyboard midi controller from MAudio and connect it to your main keyboard like Motif or Tyros and get the sound from it. There are thousands of sounds from it already. I don't know how effective it is. I haven't tried it yet but I know it will work.