Note to Mr Malenfant - I haven't a clue about the "shape" of the magnetic circuit involved, but there have been comments that the Jico general Shure stylus replacements (not including the more bespoke SAS models) sound livelier than the originals. This could be due to all sorts I suppose, but I suspect the magnets may be more efficient and tubular in section, whereas the Shure originals were "diamond-shaped" in cross-section. This may not make any difference for all I know.

I know there have been negative comments regarding the Mexican made Shures, although the M44-7 (their highest output one I think) must still be selling, as it costs double that of the Stanton and Pickering models (who also do a juicy version of the 500/Red Hot Needle at least).