Steve - No I don't have a MIG aluminum outfit. Not much interest in stick welding aluminum either. (I used to oxy-fuel weld aluminum before I got my TIG setup, and am so glad to get away from the corrosive aluminum flux.) I do also have the oxy-acetylene outfit, but it mostly sits and gathers dust now.
Jakeru, don't write of the O/A completely. I still use it on occasions. I just picked up a couple fresh tanks today along with a couple of new 250cf Ar and He bottles. Ka Ching.... Helium is expensive but you'd be suprised how much easier and faster that 1/4 and 3/8 Al TIG's with a 80he/20ar mix. You still want to get that Water Cooled Torch though.