Perhaps to clarify a bit. Rust Reformer is not technically a paint. Paint is something that forms a separate layer above the coated surface, with the intent that the layer will stick to that surface and protect it. Unfortunately, paint does not stick well to the torsion bars because the surface "squirms" as the bars flex, and the layer flakes off. As you noted, the TM's iron frame members don't squirm, so paint sticks better there.
. . So how is Reformer different? The iron at the surface of the torsion bar combines with oxygen from the air to make iron oxide, aka rust. Rust Reformer does not try to create a protective layer on the surface. Instead, it chemically alters the original surface into a different chemical form that does not react with oxygen. In technical terms (aren't you glad you asked?), the converter changes (converts) the iron oxide surface into iron phosphate, which does not combine with oxygen. It works well. It doesn't last forever - eventually the squirming of the surface opens up microscopic cracks in the phosphate, allowing oxygen to contact the underlying iron. But this happens a lot slower than with fully exposed iron.
. . Yes, I use the term "iron" instead of "steel". But steel is around 99% iron, and it is the iron that rusts. So to answer the original question - if you clean off the existing rust, the Reformer is a good addition, and will look much better. But it won't last forever.
