Unity and UE4 are also free realtime engines. Unity works especially well with SketchUp. The advantage with Enscape is it works directly inside of SketchUp. The advantage for Unity is all of the 3rd part support for shaders, animations, canned effects, post effects, VR and the list goes on.
Here's a few Moi3d -> SketchUp -> Unity renders (and HTC Vive Vr):
