I fitted a acccuspark unit to my spitfire, worked well for a few years, then car started to misfire. Replaced with points and condensor and all was well. I haven't bothered with electronic ignition again, I don't think they are worth the bother when I only cover 2000 miles a year!
Had a complete failure with a pertronix unit on my 2500 saloon only lasted about 18 months, now on points and condensor.