[ The most recent U.S. Kn-2600's come with a card reader as part of the package. The Kn-2600 has a slightly uprgraded sound system, a few more sounds etc. If you are into playing audio files, MP-3's etc, and mass storage the KN-2600 is the machine.
The KN-2400 has the disk of course, and that is a big advantage for those who are not into card readers etc....for example, most everyone can download standard midi files from the web and use the disk drive.(don't forget the 2600 lacks the disk drive)!

I can mail you a flyer for both keyboards if you like...for U.S. customers we have the KN-2400 at $995.00 + shipping.

Greg