Daz3D has worked great for me. I used on my project in Unity and will use it on UE4 for High Poly Cut-scene version of the character. I used it for reference pictures when Sculpting my Lowpoly model in Zbrush. It also great for NPC and making quick prototype lead characters for levels
https://youtube.com/watch?v=Ao7RRCyvBYw
They can be great for character customization as well