I had a Petronix III distributor fail on me after 20 minutes, the rev limiter would kick in at 4000rpm. I tried all the checks and adjustments that the Petronix rep told me, but still no good. I had to return the distributor to Petronix at my expense (Australia to California), and after 4 weeks I received a new distributor. I have not used it, since I ended up buying a MSD distributor which works well.
As mentioned, the Petronix distributor is taller than both a factory or MSD distributor.