Well I have the Tyros 4 and I don't need any more keys OR the hard drive LOL I prefer to record directly to the USB stick. That said IF Yamaha had 8 Track audio Recording instead of two I would go for the Hard drive. Also if Samples could be loaded from the HD I would prefer one as well.

BTW I had a PA2x for about 4 months and sold it for the Tyros 3. I bought the Korg for the wrong reasons.