I have Vray next right now, it is working nicely, I do mostly product renders, nothing fancy. My main reason to upgrade would just be render speed? using 3080 12th Gen intel. Should I be using RT or CPU? in such cases is an upgrade warrened how much faster should expect.
Thanks!
I tested once 3.6, next and then 5 with a renderscene I had and found, that 3.6 was the really fastest one (dont know, but it was roughly 10-20% faster then the others which increased rendertime by every nee version)
But there was also the inplementing of the denoiser in Vray next wich helped me out on getting fast renderings either then. try the trial and see by yourself. 
i tested demo verses 4 it seemed hybrid was faster