Is there a best cartridge track force gauge?

Elizabeth, some tracking force scales make much out of testing tracking weight at record surface height. These scales seem to be .6 and .75 inches thick. Do you make any effort to somehow test tracking force at record height? Do you have the 50 gram to .01 gram scale or the 100-.01 gram scale?

If the stylus were elevated 0.75 inch, and the arm was 10 inches from pivot to stylus, the arm would be off level by 4.3 degrees.

Cosine of 4.3 degrees is 0.9972

So a VTF that ought to be 2 grams will measure as 0.9972*2 which is 1.9944 grams.

This is an error of 0.0056 grams.

Big deal!

It strikes me as funny that vinyl fans, who usually discount all forms of measurement and insist that only listening tests count, should fuss so much about accuracy of VTF scales. Of all the audible characteristics of pickup setup, VTF is the easiest to optimize by ear.

Of all ... setup(s)...VTF is the easiest to optimize by ear

Actually, I agree -- as long as you don't get carried away over (or well under) the limits!
But a reliable digital gauge is useful to re-set a cartridge to an optimum setting found in the past.

Eldartford, my arm is spring loaded, the Ortofon, in this case the spring load would be off by more than you suggest. Generally, I agree that your ears are the better gauge, but there are interactions with VTA to consider also. The Ortofon cartridge at least in this arm likes a positive VTA (up in back). I have no idea why this is true.