I see. It's impressive, but I think because Karba is a good 3ds max user ;-)
Impressive details, modeling, roads texture, Multiscatter and MadCar simulation.
We can obtain th esame with VRay or Corona "without" problem.
In this case, the renderer is just 20% f the final output.
But yes, 5 minutes in HD ready is very cool ^_^ (x4 titans)
Also, without post (SSS, MB, real fog, lens effects, Color correction etc... )
But the most important thing is: everything less than 1.2Gb O_O
I never did any heavy exterior scene in Corona, But I did many with VRay.
with this scene, pfff.. with VRay you can use easily more then 16 GB!
In attachment the RAW