Hello,
I am not sure what stories you have heard but this system works perfectly well with all power levels. I am yet to experience any complaints from anyone with missfires at any power level.
We did had some issues with dwell time on revision 1, but that was fixed years ago and all drivers sold out into the marketplace upgraded free of charge to revision 1.1
Dont forget that with your P8 you can run the buiilt in drive system with a simple chip data change, although that will render you with no tach drive so you will have to spend some extra on a tacho if some wires and diodes dont work. (They often do)