A-arms simply provide a force on the shock over a certain distance. The only thing that differs is lower shock mount placement, and the length of the lever Arm. there is no Reason that Elka PEP or Works for that matter couldnt make shocks for these A-arms. I have taken 3 years of marketing, and this smells like a marketing tactic. I dont think Axis can legally reserve the right to use Custom Axis specifically. once they are in your posession anyhow.
Does Custom axis have more R&D time with that front end? Probly
Are they good A-arms? From what I have seen Yes. They seem to be up there.
Does this have any Relevance to your post? Not really
but I thought I would share my thoughts on the ARS-FX setup
You can probly find some cost effecient alternatives to these though.