Quote: "a unified lighting engine built in is worth it in my book"
I couldn't agree more, I've been trying to produce a unified lighting and shadowing engine in DGDK and have failed likewise.
However, I'm going to spend some time learning to program the DirectX API directly and give it a while to see how people get on with the Leadwerks Engine. I need to see it working in a real game level environment being pushed hard and stretched before I decide to invest time in it. As to the price, if it delivers what it promises then £75 is CHEAP!!!
No matter how good your code is, someone will improve on it