I came because of the API and that it doesn't force weird abstractions on my code. The crappy abstractions are very disruptive between the layers of code. I can do c# in my sleep but I leadwerks is still more of a joy.
Marie (my wife), the 3d artist I am working with is very realistically 4x more productive with Unity3d then with leadwerks, and it is scary how real the productive gain is. It pains me to trade my joy for hers. It's not fair.