At the level that such cartridges like the higher tier ZYX, or any other high quality brands, of course VTA-SRA is going to be important.
And so will proper exacting overhang alignment, azimuth angle, zenith angle. Without any of them properly set, no top notch cartridge is going to give you all it can.
I would say of all the adjustments, SRA might be one you can sort of "wing" and get away with, without driving yourself nuts making micro-adjustments for every single record that gets on the table.
I'm not saying it's not an important adjustment, and yes, by not having the capability of VTA-SRA on the fly, you will lose out to a degree, that certain records just might not be sounding their very best.
I have found with my own Airy 3, that once I had properly set VTA-SRA, it wasn't something that urgently needed addressing per every record that got on my platter. That even though I don't adjust per record, my Airy 3 sounds stellar on virtually all my records. Sure, not every record is going to sound like some Blue Note Re-Issue, but that's usually not the fault of the cartridge, or due to poor-improper set up. The Airy 3 won;t candy coat a miserably mastered recording. It will lay bare what's on the record.
To sum it up, yes, the cartridge will surely benefit from precision set up in all planes, and adjustments. But will the Airy 3 then be a cartridge that will drive you nuts, and sound horrid because you were either too lazy to play with VTA-SRA on a per record basis, or have an arm that does not incorporate VTA on the fly? IMO, no, it is not that hyper sensitive in my experiences.
Now as far as protractor alignments, and in regards to precisely accurate overhang, zenith, and azimuth, yes, these are highly important that they are correct, and as precise as possible IMO.
I would recommend a high quality protractor, and the MintLP Best Tractor comes to mind per any arm-cartridge that's out there if you want to get the very best from it. Mark
