What about Uni Din?

I have used the pro version of that protractor for quite a few years now. The Uni Din can be really good. I like it on my FR64S, but in truth I haven't developed a metric for when to use it or not. Try it on for size :)

I also use the UNI-Pro version, the big brother to the SMARTractor.

I like it. It works well for classical works that have complex climactic third and fourth movements. .

Here’s Fremer on UNI-Din playing off an excellent chart from Wally Malewicz. But he doesn’t talk about listening.: https://www.analogplanet.com/content/uni-din-versus-l%C3%B6fgren-b-just-clarify

Thanks guys. I'm will try to evaluate it but not having two arms at the moment might make it difficult. My own feeling is that for the vast majority of records ending by 65mm Lofgren B is going to be the best.
Raul, the inner null point of Uni Din is at 63.3 mm. 
jtimothya, I do believe Mr Fremer's graph is mislabeled. The Y axis I think is degees of error not Harmonic distortion although the two are most likely related. Notice at the null points it is listed as Zero. Harmonic distortion is never zero.
If you were really interested in inner groove error I think you would go with Stevenson. Some of my older classical records do run darn close to the label and the big crescendos are always at the end but this represents maybe 1% of my listening. I love string quartets.  

Mijo, You assume that at the outermost grooves the increased stylus velocity compensates for tracking angle error. That is actually an interesting question. I am not so sure one can assume that your assumption is correct. They are two different phenomena.

Dear @mijostyn : I'm not talking of null points, this is what I posted that is one of the input values to make alignment calculations:

"  alignment you are talking about choosed the most inner groove distance around 54mm. ""

R.