A3Zab,
I think there was in A320 older msn's the NAV AOA DISAGREE msg, but not sure.
Newer versions have the NAV ADR DISAGREE msg which includes speed or alpha disagreement. However I thought that for this msg to come up would require an ADR firstly to have been failed or rejected by ELACs.
As for the DISCREPANCY msges, I am new in the bus, FCOM doesn't clarify this but makes a lot of sense. Do you know the tolerances for the IAS msg between PFD's? Thanks