Why is it that everytime someone comes up with a workable CDI ignition they have to go nuts and start seeing dollar signs? Then go into endless development- paring down the design til' it hardly works and finally declare they are "in business" and then get a flood of orders that they cant keep up with- then 2 months later give up and quit selling altogether?
Someone needs to give up a solid design- PRINT IT RIGHT HERE ON THE BOARD- with easily sourced parts- for the good of the community. It's not like everyone on here has the capability or desire to assemble one anyway- it is not gonna "kill" the well established ignition makers.
But alot of us do want to make our own. And would if a proven design were available- and I ain't talking about those same old sketchy designs people get pointed at when they ask this question- if that crap worked- we would all be flying it-

A simple CDI with good, efficient characteristics- and maybe upgradable to add an advance feature for the more accomplished builder.

There is no reason why one should cost more than 25-40 bucks total if you sourced the parts and built it yourself. Most of us have half the parts already lying around.