Thanks for the interesting quotes from Shure. Companies post what they think will sell product, but this is worse nonsense than usual.
Most phono cartridges use Mumetal for the cartridge body; MuMetal acts as a magnetic shield, thus shielding the internal mechanism from outside magnetic influence and vice versa.
Shure conceded they have no experience with MC's, so this self-serving statement is pure speculation. It's also untrue. Like many A'goners I've used dozens of LOMC cartridges from multiple manufacturers. Their magnetic fields all extend well beyond the cartridge body.
* FYI - Stainless steel has no, or very slight, magnetic properties.
Self-serving, generic and metallurgically inaccurate. Most non-austenitic SS alloys are attracted to magnets. The strength of the attraction varies with ferritic content and the polar orientation of the molecules within the object.
Multiple owners report that some (but not all) SFG-2's are attracted to magnets (mine isn't). This inconsistency could be explained by inadequate materials sourcing specifications at Shure, which would be consistent with Shure's assumption above. If Shure neglected to specify austenitic SS then some magnetically attractive gauges could have resulted. Non-austenitic SS alloys are generally less costly, so that's what Purchasing or a supplier would choose unless Engineering specified otherwise.
It's easy enough to check yours of course. Just put a magnet near it. :-)
If it is magnetic, the risks of using with a LOMC are twofold:
(i) magnetic attraction between cartridge and balance would invalidate the accuracy of the measurement;
(ii) magnetic attraction might yank the gauge into the cantilever and damage it (unlikely, not impossible).
If you have a $500 (or $5,000) cartridge, why skimp on a VTF scale?. Good electronic ones can be had for $60 or even less. Search here or on ebay.
