A little FYI, generally pure CO2 is a LOT cheaper than "Gold Gas" aka Argon and works for nearly everything you'd ever need it for. If I recall correctly, Argon is needed for very heavy/thick welds and is over kill for anything thinner. Definitely research it out, or just try it some time, but my dad runs CO2 for just about everything he does. He mainly welds around 1/4in or smaller though. Also the local air gas store charges very little difference between tank sizes, so best bank for your buck is the biggest CO2 cylinder you can get. Smaller ones are nice for lugging around though.
I keep seeing that 350x sneaking in some of your photos =).