I have 2 of the Kore 1 controllers - I wasn't that convinced there was so much better a difference about the Kore 2 controller to buy it - but I did upgrade my Kore 1 software to Kore 2. NI decided to switch to the Machine as their controller concept - that's my understanding. I liked the idea of being able to control all the different softsynths and effects with a universal controller - but I think it was too technical and difficult to configure for all but a few dedicated users. I think too that it sucked that NI would come out with that product, upgrade it - and then promptly abandon it - leaving everyone that bought it screwed into the future - but I've been thru that before plenty enough.
Sometimes when something is discontinued - it's even more expensive. It all depends. I sure wouldn't part with my Kore's for less than I paid for them - and they weren't cheap.