It is not logical to have all the features of the Gynesys in a keyboard for 2500$. I find the Gynesys sold at 4000$ very reasonable, because just the addition of 64mb ram of flash and a CDRW plus the hard disk, that makes an additional cost of 1000$ and I heard that it comes with 100 watts speakers and that is also an added value for 400$ plus all the marvellous functions, good quality of sounds and styles... so 4000$ is not too much after all for such a keyboard.
For me I will buy it even if it cost 5000$ and this is the opinion of my friends because with the Gynesis I doesn't need to buy a second keyboard and that is also an added value.