Carol,
Unfortunately, the G600 is like the G800 which were both very disapointing keyboards to me. The G1000 and the EM2000 added many significant upgrades. One of the major upgrades was a good internal sequencer instead of a direct to disk sequencer, and they added the zip drive with direct disk playback of styles and songs. They also added to the basic GS sound library (which is what the G600 has) many hundreds of pro quality sounds. You can still buy the EM2000 which is the same size keyboard as the G600 (61 keys and built in speakers). Selling price in US for a EM2000 is approx. $2400.00. It is much more expensive then the G600 but it is so much better.
George Kaye
Kaye's Music Scene
Reseda, California