Clint: If your looking at overhead or vertical welds with a stick, DC is hard to beat, although it can be done with practice using AC. We have an old Miller AC, still a good welder, and a 80's era Century AC,DC. We use the Century all the time as most of the implement manufacturers use higher carbon steels and a DC welder works good on them, (Low hydrogen rods) One thing I would look for though is infinitly variable output as the presets on the cheaper ones are never quite right for the heat you need. Look around at farm sales etc. a good 30 year old Lincoln or Miller is usually a good buy. They used copper wound transformers and large diodes with heat sinks, made to last forever. They usually have a better duty cycle than the newer ones do to.
