I too use Alumiweld from Harbor Freight ($8 and change for about a dozen rods). I use a wire wheel in my grinder to clean the work. For light stuff propane is ok, but mostly I use Mapp gas. I find it keeps the working puddle more contained because it doesn't take as long as propane to get to right temp. Rod has a high tensile strenght, but doesn't like vibration. I try to avoid butt joints, favoring lap type if possible. Still my advice is to practice a few times, 'till you get the hang of it.
Good luck, red