It's ridiculous ( for say the least ) that almost any one of us own not one but several after market jigs/protractors because the one that comes with the tonearm is not ACCURATE or not user friendly.
IMHO, this is the major fault of almost all tonearm manufacturers. If these manufacturers make a good Jig/protractor then no one of us could want any after market device. That JIG is not " rocket science ".
That tonearm/cartridge JIG is critical and an obligation by the tonearm manufacturers.
That's the " perfect " audio world where we live!.
Regards and enjoy the music,
R.