Hi, I have a GEM WK8 arranger keyboard. I really love it. I'm planning to buy a 88keys (weighted) keyboard with very good piano sound (the piano sound is not very good on my GEM). I want a this second keyboard also to be the controller keyboard for my GEM, so that I can play on the weighted keys and keep using the styles/sounds/functionality of my GEM.
1) is this possible (I'm not a midi-specialist)
2) what second keyboard would you recommand? The Yamaha P80, S80, the Roland A90EX, the Roland VX-88, the Roland RD600 or RD 100,...?

Please help my, because I'm not familiar with master/controller/keyboards or synthesizers...

Thanks a lot for your Advice!