On my street cars I use a capacitive discharge ignition system with a magnetic trigger (either an HEI distributor with the HEI module disabled, or a crank trigger). I have two MSD 6ALs and a MSD 7AL-3 that I have used for over twelve years now. I have read reports that MSD shipped their manufacturing over to China, and the quality fell considerably. Couldn't say as mine were made in the USA. MSD invented the capacitive discharge ignition system for racing two cycle motor bikes which are hard on plugs.
GM later bought them out to use their devices to reduce emissions. Frequently reducing emissions and increased power go hand in hand as nothing makes more power than burning all of the gas you dump into a cylinder, or by making a head breathe better by raising the ports (Chevy's 1996-'04 "Vortec" heads), or mixing the gas and air to get complete combustion (Chevy's "Fast Burn" heads). All of these changes to early Chevy heads (designed in 1951) were advanced to reduce emissions: but they also increased horsepower.
A capacitive discharge ignition system burns the fuel more efficiently by firing the plug two to five times every power stroke. Even when at high RPM it only fires once, the spark has much more power as the juice to fire the plug comes directly from the battery, not from an HEI transistorized module. The bigger the number (6, 7, or 10) reflects the size of the caps inside the box and as such the power that they can soak up from the battery. A 10AL has enough power to kill you if the surge were to travel through your body (we are talking about amperage: as anything above 28 volts can kill you; and your plugs fire with thousands of volts, but very little amperage with points or HEI inductive ignitions). A 10AL system is the equivalent of a mag in power output, which is why they are used on race cars that used to rely upon magnetos. Advantage is to the capacitive discharge ignition system that doesn't rely upon a mechanical contactor to fire the plug (points) the way a mag does.
Big Dave