Hi Dan,
The reason that KeyShot is fast/simple and produces great results is "That's what it was designed for". Simple fast photo realistic output.

The others have user definable areas that dont exist in Keyshot. This is the tradeoff. I can get basic results with keyshot. The others have more user control and definable properties.

You pretty much explained that pretty well. If keyshot had all that built into it also, you would have to spend a bunch of time digging through it also, to find what you were looking for.

It's kindof like, render a ball with keyshot = 2 click's. But try to render a "TREE" with keyshot.