problem with the MSD stuff, at least for hondas, is it overcomplicates and already simple system.
Ask scotty, we have seen more problems out of MSD than a stock setup.
As long as you have good heat range plugs for your application, NGK Wires (the simple blue ones ), and a healthy distributor, nothing is needed till you cross the 400whp mark.
Some poeple get lucky, like i think Spoolins first car did 600whp on stock distributor haha