Why not offer dual mono and 3 supply 3 channel as an option?
Not at that point in the business yet. Would require another set of boards/inventory to carry. And higher purchasing quantity per order for the SMPS. Which would cut into the purchasing power of my existing products and affect pricing, lead times, etc.
The main goal has always been to offer these amps at pricing that is at or below others. A dual mono would, in all honesty, give no audible improvement or advantage in real world usage for the effort and cost involved for me to bring it to market.
If I end up going the Micro Audio route for the 3ch and someone wanted to nitpick they could request the same SMPS in their 2ch build.
I am not too concerned about it as I have, to date, had zero people take issue with the 3ch Purifi only using a single SMPS1200.