I'm just curious as to at what point should you upgrade your ignition to an MSD, Crane, and the other's that are out there? What is the benefit of having one? I know that it creates more spark, and some of them can retard, and advance timing when boosting or shooting nos... but if you don't need the timing feature wouldn't a good set up spark plugs work just as good?

I have an MSD 6AL with an MSD external coil, and I'm wondering if I really need it.