I use 1/2 and then a short 3/8 to the 1/2 impact, a 1/4 whip on everything else. I have one UGLY old IR 3/4 that I dig out for the big stuff, and "hard" stuff, direct from 1/2" I think there's only been one rusty, huge old nut it would not remove, I don't remember what that was. It is a brutally awesome piece of ugly
When I sold parts, the local truckers--mostly loggers--started tapping into the rear air tank to change tires. One guy came back with a 3/4" he said just didn't cut it. Asked him what size hose? Turned out he was using 3/8. WRONG LOLOL