Don, I've had a 6A on my 57 Olds for about 20 years and it has yet to miss a beat. I also upgraded my points distributor with a Pertronix Ignitor and a MSD coil. Whole system works well together and eliminates 99% of the ignition problems that I had before.

A lot of people that I have talked to prefer the 6AL over the 6A because it has the rev limiter. A little more money for extra protection.