I used CDI power packs on my 78 Johnson. No issues. I also bought a CDI dva adapter for my DMM. Seemed to work well. I also had great luck with Arieltek products for OMC. I used Arieltek on my 87 Johnson and they were a tad cheaper than the CDI, way cheaper than oem.
CDI several years ago supplied BRP their replacement electronics but that has went by the wayside. Since CDI went to outsourcing their mfg the quality of product has declined IMO. That why I use Serria as best warranty in industry if you have a repair operation.
Think Arco might still have their production and repair operation, unless they have outsourced that as well. Some years ago, I had good luck with their products (inboard starters, in my case). Customer service was excellent.