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Transistor ignition is also known as inductive ignition due to type of coil used. CDI was all the rage back in '80s when aftermarket programmable EFI systems because more accessible. One of marketing hype with CDI was "higher voltage", but that doesn't automatically translate into better ignition.
Main problem with CDI is short duration. A lot of times, it'll ignite mixture, which then goes out. One of solutions was to fire multiple-sparks and MSD was born. It's all fixes and crutches for an ineffective system really.
Modern hot-rodding tends towards high-capacity inductance coils (measured in milli-henry). These coils store a lot of charge and when dumped through plugs, it generates a hot spark that lasts much, much longer than CDI, and ensures you have ignition and complete combustion.
With advent of COP-coil on plugs, even higher capacity charge per cylinder can be delivered because coil has entire 720-degrees charging time for just one cylinder. Rather than having reduced charge due to sharing with all cylinders.
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