That price is totally worth it though. I'm finishing up a first version of my own (native) C++ 2D engine. It runs smooth on iOS and Android, PC and I'm going to get it running on Bada, WebOS and Mac OS as well. The time it took me to get this up and running is around 1000ish hours, and I'm pretty experienced in the area. Going to put in 3D as well soon. :)
I'll be adding lua as a scripting language, but it probably won't be in v1.
That said, I don't really want to take the same direction that unity is currently taking. Since the engine that I wrote currently pretty much works on every mobile platform, I'm aiming to sell source code licenses to game companies.
It's pretty expensive, but given how well that demo worked i'd probably buy it if i did any javascript.