Keyshot is an excellent program, I haven't had time to experiment with it myself, but it looks really simple to use.
I do think you have lighting and surfacing issues though. The car is stronger lit that the environment and some of the shaders are picking up crisp reflections which look unrealistic. The car's slightly too reflective imo, so you're killing alot of the realism in it by making some of the dark blacks completely gone. As a car artist within the games industry I suggest baking out an AO pass, and using that to maintain your natural darkness. A reflection fall off on your shader should also be looked at, cars don't have perfect reflection like an HDR reflection ball. Reflections should be nice and clean, not stretched.
Also watch your geometry, some of it is quite wavey which causes the distortion you will see in your reflections, another reason why you may want to dial down the reflection. Keep it up, you've progressed well from looking at your other works.