I have had an "off brand" (Century, sold trough Snap On) for about 15 years and it has performed very well. I had to replace the gun twice, other than that nothing. It is a 220/205 amp.
At work I use a small 110 volt Miller 130. I HATED it at first, but after getting use to it, I now find that I enjoy using it. I weld frames (1/8") with out a problem.

1948 Chevy Pickup
Chopped and sectioned
owned since 1974 when I was 15.