We’re using RT for more than a year and a half.
In fact, I’ve founded the whole company betting on the RT technology, so we invested purely in videocards. And it’s been a lucky bet 
We’ve been experiencing with a few other RT rendering engines, but we considered Vray as the most reliable based on ROI(return of investment), even if at that time it was quite/really buggy.
We don’t even consider using Vray Advanced. Actually, we never used it in 1 and a half years(when the company was founded), except doing some masks for a few scenes. Basically, our computers never seen Vray Advanced 
RT is the future(even if it needs some further developing, but i hope things will be fixed progressively and soon) so i don’t even think going or looking back to CPU rendering.