This is a classic case of “Dont let your eyeballs fool you”, the only difference between the two images is the tone-mapping curve applied. Thea has a tuned tone mapper built in where as vray assumes you will do your own tonemapping (such as in adobe camera raw assuming you’ve saved your images as 32bit float). As you get into larger scenes and more advanced shaders, vray will outperform thea in every situation and is more stable, it is production proven and bulletproof. I did a quick pass at the vray3.4 render with camera raw. Granted im working with a crap jpeg compressed 8 bit image, you can only imagine what Im able to get if I had the original 32bit image.
when it comes to modern rendering, understanding color space / color science is everything.
