I have the original ignition system in all of my Stovebolt engines. I have always purchased top of the line Napa or Delco ignition parts and knock on wood I have never been stranded because of ignition part failure. By design these ignition systems require periodic maintenance. I do have a Pertronix ignition conversion in a '47 Flathead that I own. I was stranded with that car because of a condenser failure. By design with the distributor mounted to the front of the engine access to fix it alongside the road is difficult at best. I have been very pleased with the Pertronix system but have learned a few things over the past 5 years running it. The system needs a good ground and also a good constant voltage supply. I have a ground wire attached to the side of the distributor. I had issues with the car stumbling at times, especially at night when I needed the headlights. I did some testing and found that my generator was working as it should but did learn that it just didn't have enough to keep up with headlights, radio and the demands of the ignition system. I installed an alternator earlier this summer and have since solved that issue.
When it comes to ignition and voltage some standard practices go a long way. The power supply wires and ground wires need to be in good shape. The connectors need to be properly crimped to the wire. I have seen so many guys twisting wires together or using poor quality connectors, they lead to trouble...always. One last thing is to trace wires to the point of origin to make sure a complete circuit can be made. Wires that have been added to usually end up with a voltage loss because of poor splices, bad connectors or improperly crimped connectors or junk wire added. Sometimes the little things go a long way to having something work good.
Don