Power Service, silver bottle, from Autozone.
The PS white bottle is labelled 3 Cetane points improvement plus anti-gel for cold weather, while the silver is 6 Cetane points and no anti-gel. (I don't need anti-gel in this mild climate.)
My older 2 cylinder Yanmar starts, catches, better with the PS in the fuel. I think it clanks less and runs smoother, and the exhaust is less obnoxious too. Its owner manual specifies 45 Cetane fuel minimum while the US Standard is 40 or better, so I think the PS makes the fuel closer to what the manufacturer intended.
My smaller newer Yanmar, 3-cylinder, always starts instantly like a gasoline engine so I don't bother with additives in its fuel.