Buy the Sullivan Model 4. Run it on two 500 amp batteries. It comes stock with the MillerRC 3" reversible silicone insert, and runs the US 41 at 2400rpm. You don't choke, flip or any of that. You place teh cup of the starter on the spinner and touch the trigger. The US 41 starts in less than a second, with no priming, as the carb's diaphragm is activated by the starter and fuel flows fast. I do flip a few times until I feel the gasoline start to loosen things up, but that's it. My cowl has no cheat hole for priming or thumb-choking, and the velocity stack is bigger than my thumb any way.

As well, you will never buy another starter again. I have a friend at the field who uses it on his
DA 100, and with the sweet ignition that engine has, it's a dream.

greg