I'm considering adding CDI to my OS Gemini 120 twin. It will use less fuel, gain more power, and use less oil, while still running on Glow fuel. It's already a heavy engine, so adding 10 ounces wont make much difference. I think it may be a good fit for my .60 Corsair, which will need all the nose weight it can get.
I found a kit from the UK for $143 plus shipping. If over the life of the engine I use 10 fewer gallons I will have saved more than it costs.