I Switched From the NVDIA IRAY Engine to 3Delight and Everything Now Works

Formulaone

When I was using the NVDIA IRAY engine I couldn't, for the life of me, get my lighing to work AT ALL. As soon as I switched to the 3Delight engine, everything instantly became easier. Lighting works, Shadowing works, Rendering is super fast in comparison. I've included a couple of my recent renderings using lighting. The first one uses only one light; the second used two lights and has two sets of shadows....Very interesting results

Is NVDIA a better overall renderer? Higher quality? Why does it seem so difficult to use?