I haven't. Friend of mine has.
The air to fuel gauge is way more sensitive than what is needed for most carbs. What my friend was doing was custom tuning. Basically changing power valves, needles, jets.
He would do it along side the road. He would drive, check the gauge at different rpms and loads. record it on a tablet. Then make changes and start the process over.
Not sure most people would notice most of the differences but he definitely got the most out of the engine.