I purchased a Lincoln Mig Pak 10 from Eastwood several years ago. I really like the Lincoln welders and it has lasted quite a while without any problems. I had a Hobart welder at one time too, and it worked well.
Only difference I found between the Lincoln and some of the other cheaper welders is that the wire was hot at all times, with the lincoln you had to press the trigger button for the circuit to complete. So you can put your wire right down where you want to start, the flip you hood down and go. I got a few flashes in my eyes before I got used to it with the Hobart.
I agree with Tim though on an arc welder. I wouldn't use one on thin steel. Not only do you have to worry about burn thru, but there is a higher chance of warping the metal. I've warped metal with a grinder before, it's no picnic when it is in the center of a door you are trying to put a lower patch panel on. Live and learn.