MSD, can you tell the difference?

I ran 3 different boxes on my Dart, all of them failed by just shutting off eventually so I always left my stock box in place and have quick connects on the coil wires and things in case I have to change it out.
Died on me at a light one time and I swapped the wires over and had it running almost before the light changed.
Maybe my wiring's all fubared or something but I haven't had one last longer then 6 months yet.
The car ran better when it did work, and started great but I finally gave up and went back to factory style boxes.
Even had a couple of the old 404bc direct connection boxes and once I got the thing started they idled and ran way better but the box was old and had issues as well so it never started quickly and needed at least 7 volts just to throw a spark so I had to bypass the ballast and all that, plus narrow the plug gap.
Great idea when working but frustrating for me to run. I'd love to get a 6 or a old 404bc that would just stay working...