I have a D1SC ATI PC unit with an 8 rib 4"pulley installed on my C6 - it produces about 11-12 lbs of boost. With the other mods i have to my top end I am producing approx 675 crank HP. I use this car as a daily driver and all you have to do to wake the beast within is step on the accelerator hard. AND mark my words, you want to be careful when you do this is both first and second gear!!! Unless you are literally stomping on the gas pedal, the car performs very much like an every day stock C6 - that is the beauty of the PC DISC unit. The other interesting thing about these PC units is IF you heavily mod the top and bottom end of the engine and shorten the pulley you will get some really serious 800-900 +HP gains. Don't know what an "F1" unit is?
Never heard of a by-pass being available or why you would need one - unless you have a lead foot.