If you have no idea what Vias is (Its not Vls) then I hope to God i am never a passenger when you are flying the bus
Well I've been flying it for 5 years and I don't know what VIAS is. I think he means the IAS target that g/s mini computes during the approach. Airbus never refer to this as VIAS in any of the documentation that I have (paper FCOMS and searchable CD ROM) but do call it either IAS Target or VAPP Target. Perhaps VIAS is a company name for the same?.
Interesting thread this, I now fly all three narrowbody Airbus a/c and still much prefer the 321 over the other two. Much nicer all round than the 319 and 320, it feels more stable and planted in all stages of flight and I find it easier to land consistently than the other two. It seems easy to "over flare" the 320 and 319 but the 321 just sits down nicely in the right place pretty much every time. A few knots entered in the perf page can certainly help if the bug is a little near VLS during the approach in strong x-winds for instance.