Disclaimer:
I don't own and have never used a Kemper Player or ToneX. I quit using modelers years ago when I upgraded my Line6 POD xtLive to a POD HD500 and went back to amps due to a serious lack of satisfaction. Two years ago I came across a good deal on a Kemper Stage and my amps don't get much use these days. A year later I bought a Kemper Rack and a Fender Tone Master Pro, sold the Stage a couple of weeks ago and then the Player was announced. I've been looking for info on the Player and decided it's not something I could use because I don't play out anymore and I have no interest in pedal boards. I considered getting a Player to use with my Pedal Steel Guitar just because of the size but I can use the Rack and iPad just as easy and not limit the number of FX.
Having said all that, if I were to by either unit it would be the Player. because ...
1. Kemper has 110 FX and the ToneX has 4 . Kemper has 27.5 times the FX for a price difference of $300. That alone seems enough to justify the cost difference. Plus, upgrades paid and free will be coming for the Player, idk about the ToneX.
2. Kemper offers 4 USB in/out audio interface ToneX offers 2 USB channels in/out.
3. Kemper is designed for an external screen, which for me means easier to read from an iPad on a stand rather than a small screen on the floor. Not to mention easier to tweak settings or select rigs or use Bluetooth for backing tracks.
4. As far as "more accurate profiles", the sound difference is almost undetectable to my ears on what videos I have seen. I have no way to tell what they sound like live in the room.