Its up to you
Mine is aftermarket and i like it so far.
Distr. cap will wear off much faster with high powered system. Also old style caps will be performing much worse than newer style ones. Wires will burn out faster, unless they can handle load.
Most important of all - if you keep your plugs to be Bosch 2+, 4+ - you wont see much gain, no matter what. With regular geometry plugs you got to increase gap a tad. More powerfull spark is nothing. Longer initial plasma arc however gives you whole lot of benefits. But thats up to final manufacturer specs.