Feickert Protractor - anyone use one?

My above post assumes the arm does not have a factory mounting template.  Buying used arms typically eliminates that convenience.

I use AccuTrak arc protractors for my arms.  I have a TT where I can adjust P2S distance easily.  I think this point was made earlier, with Arc protractors you don't need highly accurate P2S measurement, just need accurate enough to get within the overhang adjustment range of the headshell. When you are on the arc you have the overhang correct.
For most cartridges where the cantilever is visible, the AccuTrak allows for very precise adjustment of zenith. Especially with a magnifying glass.  For some cartridges, a mirror would be helpful.  All this being said, if money grew on trees, I would enjoy using the SMARTractor which seems to offer all these features.

I have been graciously schooled on another forum as to the importance of the spindle to pivot measurement.  An overhang arc depends on its centre Re: pivot point to be accurately place in the right location.

I've used a Fiekert tool over the years on several tables to great success. I just bought a new alignment "block" for $50 that is another great tool when verifying cartridge alignments.
 http://www.audioasylumtrader.com/ca/listing/Phono-Cartridge/Azimuth-amp-VTA/Alignment-Block/-12-unit...