I have a renderfarm with hundreds of xeon cores. I choose UE as the only option for the future. Offline rendering will go away, and the lines will continue to blur until then. Even with the farm getting low noise, realistic animation of complex scenes in 3DS+Vray took some time. 360 frames (12 seconds) could very well cook overnite or better.
There’s too many options with UE4 to not explore it in full as an early adopter and reap the benefits that this experience will provide as the engine improves. As someone who invested in a bit of tech, and took a couple of months to look into the ArchViz, I came to the conclusion that there’s not much reason to play with what already has been played out, and saturated as a market. Better to stick to the emerging and forge it on your own.