Depends on what I'm using. Clearkote's CMW spreads nice and easy via PC and a finishing pad. But it is also a liquid wax so it can be poured unlike paste waxes. Paste wax I do by hand. Poorboy's EX (sealant, but does have carnuaba) I always apply with a PC. Klasse sealant I apply by hand. Most all other sealants I apply by PC. I actually feel I can get a more even spread with a PC vs. my hand. That's just me though :shrug:
Porter Cable becasue the $ 110 dollars investment better save me energy. Also the wax liquids last me a very long time, because of even coats and better ratio of liquid spreading. But Paste wax must be applied by hand. Pc for Optimum results :coolman:
I use a machine for the cleaning and polishing steps. I apply my final coat of wax or sealant by hand most of the time. If I am pressed for time, I may bust out the machine, but usually I'll go with hand application.
We're talking about waxing, not removing swirls. Swirls need to be removed with a PC or rotary buffer. I know it can be done by hand, but why try when you can get better results in much less time without making your arm sore?