Yes, and it is one board I will not part with ... one of my grandsons has my kn1000!!!
What's the OS like and what would you compare it to?
I've only owned two brands - technics (kn1000 and 6000) and KORG (Pa600 and 900)- but the technics is the easiest, most user friendly I have ever used ... from when I was first trying arrangers back in the early 90's, having tried Roland and Yamaha, the simplicity of operation of the kn1000 sold me after about 5 minutes, and the kn6000 was just as easy, even though it was way ahead of the curve for KBs at that time ...
KORG had a greater learning curve, but I think that was due in part to the USER GUIDE not being specific enough in its instructions ... I now think the KORG has a lot of the same 'theory' in operation as did the technics ... perhaps other boards are the same, I just haven't had experience with them ...