Ha! Super necro! Honestly, I welded up an entire exhaust for my car and steel (I know) intercooler pipes with a crappy harbor freight flux welder but using the lincoln wire. I know it isn't the best, but it worked.
I know your good welders say flux sucks, and it probably does, but my solder joints were just as effective with my crap radio shack soldering iron as they are with my weller WES51. Not that I would build a megasquirt with a radioshack iron, but for planes it works just fine. Same with flux welders that cost a hundred bucks. Would I trust it for structural integrity? No. Welding some muffler pipes together? Why not.