@holmz : " so how important is all this stuff? "
Wel, today almost only through Löfgren alignments is the way to set up any cartridge along a pivoted tonearm. So it’s way important.
Now, Löfgren alignments exist and its internet calculators ( Vlinyl Engine has other good calculator alternative. ) and what’s important is tomake the cartridge/set up as accurate we can do it. Tiny errors with the set up makes a difference for not so good quality performance. Many times we even are not aware of those errors because through evaluations listen sessions we really don’t know what to look for.
The other parameters in a set-up as VTA/SRA/Zenith/AZ/VTF and the like are way imortant too to achieve the best quality performance levels we can
Even that we can take extreme care on the overall set-up you can be sure is not perfect as always exist trade-offs due the intrinsical relationship between all those parameters where ( example ) a change in VTF changes too other parameters that you have to modify and is an almost endless situation.
So, we have to try that our cartridge/tonearm be at its best each one of us can.
Btw and I already posted: unidin is not a new alignment that could needs a especial calculator with different equations that the Löfgren alignments, unidin is only a manipulation of the input parameters in the normal calculators but forgeret that as Stevenson A is inferior alignment to the LÖfgren ones. Don't worry about.