why not TIG? It's easy to learn, the welds are stronger, and you have ultimate control. I can't say enough about the Lincoln 185. Pricey yes, but that damn thing will weld straight through paint and rust and oil, and it doesn't seem to matter what I do to the metal or what residue it has. and it is so forgiving, if you burn through, it's so easy to fill holes, edge weld, and if you don't like a weld? Just weld over it, no need to grind or even clean the old weld. I'm sure this isn't good practice, but seriuosly, you could take a coat hanger, and weld stainless to high carbon (ok I didn't try it but I did weld stainless to high carbon with low carbon rod). After grinding, I found no porosity, full penetration and the weld seam was neat and tidy.
I'll be paying it off for the next two years though. well worth it. I tried to weld a bar to a plate with a $250 sears special non shielded flux core mig and I had to clean and regrind after every 1/2" because the thing didn't like to arc to anything but pristine metal and it oxidized ahead of the weld. I strongly recommend shielded. They work well, but penetration can be an issue for thicker work, and burn through can be a hassle for thinner work.
The tig is right at home in any case, and amybe for $1000 you could get a nice used one or a DC only rig.