I have try his demo
that was amazing but also too costly unafordable price
You should see his website buildbox.com
I already saw the website but issues like eg. poor 3rd party exporter performance
(reference, see C2's features page) are never mentioned for marketing purposes.
I'm currently struggling to find a demo to get my hands on the engine by myself.
Also the price doesn't really matter if it saves time and stress with game development, my opinion though...