Contrast Detection AF is used in P&S. This enables you to focus normally by half-pressing the shutter to focus. This results in you not needing to have the mirror go up, focus, and go down again.But it still won't be faster than how the E-330/A-350 LV works.
In other words, the LV AF speed on the 420 should be comparable to P&S, and that in the E330/A350, they are in a higher league altogether?