I put the P II in the daily driver I bought with the stock 318. I chose the p II because the P I has been reported to burn up if ignition is left in the on position with engine off.

Im interested in putting the P III in my aluminum headed 10.3:1 compression, 5.6 lift 440. I wanted multispark and rev limiter, thats why I was looking at the MSD distributer and MSD box (plus later on a new motor will be going into the car). But that is almost $1000 for the pair, while the P III is about $200.

I talked to the Pertronix tech and he said the III has both functions. Im no expert on multi spark ign systems, so I dont know how the Pertronix system capabilities compare to the MSD. I just know MSD by reputation of quality, and I know I'll be putting in a race motor at some point so I figured the MSD box would be plenty for the 440 and still be able to handle any needs I'll have with the next motor, be it a stroked B or an aftermarket block.