Simulation

What if the human race grew to become so advanced that we had the tech to build giant computers that had a perfect simulations for life(and I mean perfect, everything the universe encompasses). You would live out as many life times as it took to come out with a perfect view of life and what you should be doing or how to live.
When you finally achieve this you are brought back out of the simulation and allowed to live your real life. The simulation only takes seconds and you come out with thousands of lifetimes of experience.
It would be too much for some people though as they wouldn't be able to tell if you were still in simulation even when pulled out or if it is real this time, I mean how could you know.
Any thoughts?