I bought my Miller 252 30 years ago. Other then the whip, which has been changed 3 times, the machine is all original. I opened a one man welding shop about a year after I bought my Miller. It has been welding stuff together daily, Mon-Fri until I retired 32 years ago, Now it only gets used occasionally.

About 20 years ago I bought a Miller 210 because I needed a spool gun for welding aluminum, my 252 didn't have a spool gun attachment, and buying the 210 was about the same cost as having my 252 upgraded to accept the spool gun. When I retired, I sold the 210, and got all of my investment back + free use for 15 years.

Duty cycle isn't as important welding sheet metal as it is when you start welding 1/8" thick metal, but eventually exceeding the duty cycle with sheet metal will still kill the machine. My buddy bought one of those HF welders because he was only going to weld sheet metal. He had to replace that original HF welder after the 1st year. The next HF welder he bought was their top of the line 220v welder. Its about a year and a half old and is also starting to fail. Yes, he has exceeded the 60% duty cycle on it as well. At this point he has spent as much money as it would have cost him to buy a good Miller 220v with a 100% duty cycle.

Buy a good American built welder with a 100% duty cycle. Miller blue would be my choice. Gene