When I was in my teens, I wanted a welder, I had done a fair amount with acetylene,but I longed for the capacity to build. The local business everyone in town bought everything they had from was pushing Twentieth Century, A smooth talking company rep. came to do a demonstration. He knew his stuff! This welder had features and technology the big two haven't caught up with forty plus years later. I was the youngest of the 20 or so potential buyers, so I was chosen to demonstrate that even a child can do it. With his coaching, I could! I of course ordered one. Mine an AC model, a few of the well healed citizens chose AC/DC. I've always wondered if he had something special in that red box that I didn't have in mine. It wasn't as easy as he made it seem, but I eventually was able to produce good sound welds. I've burned thousands of electrodes with that machine, and thawed many dozens of water lines. I still have it, it still works, but I haven't used it in years.
I do have a friend who does all the welding for a small excavating business who uses a Lincoln engine machine for break downs, but all shop work with a Lincoln Tombstone AC. He's a damned good welder!
