Hi Nick,

Ultimately the decision on this sort of thing is a matter of personal preference. I suggest you downlad the PSR 3000 manuals from http://www.yamaha.co.jp/manual/english/index.php
Compare its features with the KN6500 paying particular attention to the those relevant to your style of playing and then sit down for a decent PSR3000 hands on session at your local Yamaha dealer. See how it handles the things you like about the KN. What are it's shortcomings and advantages?
I have only played the PSR3000 on a couple of occasions. For my money the inbuilt speakers are fairly ordinary and as far as I can ascertain it doesn't have aftertouch. I wouldn't change my KN7000 for one and if I still had my KN6500 I doubt that I would change that either, but that is purely my preference.

Cheers
Len C.