I have a dual-quad so Fry is not bad. Actually gets pretty clean images in about 10-20 minutes. And the "light-layer blending" is so awesome, combined with very fast setup times. You don't need to worry about setting up antialiasing, sampling, caustics, etc. It's automatically done for you just as in reality. But on my wife's Macbook Pro (2-cores) obviously the render speed becomes an issue (then it's about 3x-4x slower than my desktop system). Unbiased engines are great tool to have. But not so well suited as the everyday workhorse engine. So it's good to have an engine like Vray or Modo to handle quick daily work.