There's an elephant in the room comparing the two. A month ago, Epic (Unreal Engine) acquired Quixel Megascans - a company which makes photorealistis materials.

There's an elephant in the room comparing the two. A month ago, Epic (Unreal Engine) acquired Quixel Megascans - a company which makes photorealistis materials. This scans are going to be included in for free in UE4. This is a huge deal since all developers will have access to 100,000+ sleek assets from the start.