I own one, and at first its confusing. I didn't like it at all actually because I didnt understand how it was supposed to be helpful. I came from being a heavy Motif and Fantom user and thought it was going to do all of the same things I could do on my Motif, but from the controller.
First and foremost KORE 2 is not really about that controller at all, the controller is just an extension of the concept. KORE is really about organizing your software instrument based studio and creating a quicker way of finding the sounds that you are looking for. If you are
a Komplete owner for example, all of the sounds in Komplete are automatically categorized with tags that dictate what type of instrument sound each patch belongs to. Say you are looking for a synth lead while making a track. If you type in the word lead into KORE 2, it will pull up every lead sound that you have within your Komplete 5/6 library(if you own NI Komplete), whether the sound/preset be from pro53, FM8, Reaktor, Massive, Absynth, or Kontakt. It shows you all of you leads that are tagged and allows you to get straight to the point instead of having to go through each program/plugin individually, manually loading and unloading each until you find what you are looking for.
The other thing KORE 2 offers with the hardware controller is automatic mapping of many of the controls and parameters for all your Komplete instrument presets, as well as the ability to preview and scroll through patches with the same quickness someone would if they were using a Motif or Roland Fantom for example. KORE allows you to create stacks of sounds and build a very creative new instrument using multiple instruments in your instrument library. KORE also allows you to load up 3rd party Vsts and categorize the presets of those plugins so that you can find them quicker as you work on tracks. Its a highly misunderstood product that is really designed to speed up your workflow and enhance your possibilities when working with software instruments.
I think if you own alot of plugins, and especially if you own alot of NI products, KORE 2 is an excellent tool to have to help you find your sounds and discover new sounds. It also is an excellent controller for products like Ableton Live.