When welding man'f rate their equipment it is primarily for a production environment. A hobbyist not working on a time clock can take extra steps of multiple passes after grinding away weld beads that went on cold, preheating the metals with a torch, grinding relief or bevels into the stock for better penetration...

http://www.mylincolnelectric.com/Catalog/equipmentdatasheet.aspx?p=42422

give the link a minute to load.

I use this type of welder but it has less power as its powered by 120vac. But with 220 or 230(what you would need for a waterheater/range/dryer) you get considerably more power, to make good welds in thick metal with good penetration.

Generally, for MIG, welding only steel, I use a C25 shielding gas mixture, it is 75% argon 25% Co2.

Most likely if you bought somthing like this, you would still be using it 30 years from now. Take your time when it comes to selecting your machine.

 It does use ark or stick welding rod(this has flux on the outside of the weling rod/stick). Which would classifiy it as a type of ark welding.

 Although I learned to weld with an ark welder for steel. I preffer MIG.

 'When your ark welding, it definitly takes much more skill'.

 Such as striking an ark, and breaking a fused rod(to the work peice) as fast as possible.

If you just use a filter glass[welding glass] alone to protect your eyesight, you should be at an advanced level of experience.

 Its best to use a tilt-up mask and proper filter tint selection for the type of welding application. You can easily get such help at any local welding supply store.

 I Frequently weld aluminum with a 350amp TIG/GTAW. The application uses a stronger/darker filter/tint than is needed for MIG welding steel.

Back when I was much younger, I mig welded for about 15 minutes without the welding mask{welding glass), lets just say it was tough to sleep that night, because my eyes burned like hell, all night long. Never did that again, luckily I was fine the next day.