I have the N97 and V15Vx versions of the SAS styli, and have made some effort to measure the magnet locations - they appear to be identical to within 1mm.
Furthermore my N97xE stylus came loose from its plastic holder and can now be inserted to varying degrees in the different bodies - so I can adjust for pole locations in theory - There is another older thread where I and several other people measured a bunch of shure styli for magnet location, and there does not appear to be any substantive variation in pole/magnet location.
If you also look at the Shure patents for their generator design (M3D onwards) - you will see that the pole locations are in fact a "zone" rather than a point, and the magnets need to be within the "Zone" - which allows for manufacturing tolerances that might involve the magnets being up to a couple of mm forwards or back without substantive impact on the actual performance.
The V15III/IV/V are a bit different as they have a narrower shank, the pole pieces are therefore closer together and the "zone" within which the magnet needs to be located is much more precise and limited - but then these are not interchangeable with the M97 styli.
I did a series of experiments with styli positioning using my loose shank SAS - the main determinant of performance difference was not +/- 1 to 2 mm positioning of the shank, but rather the inductance of the body itself - ie the number of turns of the coils around the poles, and perhaps the type of wire used in the coils.
bye for now
David
