What about Uni Din?

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.

Dear @jtimothya @solypsa : First than all to make compartisons between different alignments the first premise to be stricted unchangeable is the tonearm effective length, it’s not the same if we make the comparisons with the same P2S distance because the effective length changes.

In the other side and only as an example:

if we take Löfgren A ( could be B too. ) the difference in tracking distortion between the groove at 69mm and 68mm is : 0.06% .

So, both of you are saying that can be aware of that difference between two concecutive inner grooves?

No one can detect even 0.8% and that tracking distortion is going up or down at each single groove: how can any one be aware when the changes are so small and continuous? and if any one can detect it then something wrong with the alignment or the room/system.

All alignments are a compromise and Löfgren A and B perhaps have the best compromise certainly Stevenson and the mijostyn alignment is talking about  are not the best compromises.

R.

Dear @lewm  : "  They are two different phenomena.. ", agree.

Löfgren A ( example. ) distortion at 139mm is 0.19% and at 75 is 0.42%.

R.