CDI is a wholle different animal. In theory more amperage stored up to send to the coil. Prob have most of them around just cool to show peope. Dont get why people want it on thier street cars might gain .2 of a second with it.
I can see the benefit of CDI especialy with high compression. The multispark seems to work at lower rpm and a street application could benefit. I see Summit has a multispark set up. Who knows who makes it for them though.