Paul, the lack of control (four heat settings)and it just seemed to be tempermental. I still think it is, I have jsut gotten used to it and prepare the metal better and keep the nozzle clean.
My Century has 9 heat settings and it just seems that the 220 welder will burn through more contamination than the 110.
I had just left a shop with the best welder I had ever used and was more than a little spoiled. It was an AIRCO 220 running on three phase, the perfect power source for a MIG. The "Converter" in the welder that changes the AC to DC provides a much smoother flow of electricity to the tip, it would weld through just about anything! It would almost weld my its self! It was also a continuous control, and it worked great.
I recently passed a pretty strict welding test for ICAR and we used a little 110 Lincoln welder, I don't know the model number but it too worked great.
