Eldar Witchblade and Singing Spear
Concerning against vehicles only:
In CODEX:Eldar, the Witchblade entry says to refrence the BRB. The new entry for the witchblade in the 6th ed book says it has armorbane and uses the user's strength.
Here is the fun part
The singing spear entry in CODEX:Eldar says that the weapon follows the same rules as a witchblade, wounding on 2+ and S9 against vehicles.
It reads to me like "refer to the BRB for the rules, but the summary of the rule is 2+ wound and S9 against vehicles." Which is not longer the case. None the less, the paragraph does say that a singing spear is S9 and it was not ammended in the FAQ...
So, by RAW, is the singing spear S9 with armorbane since it follows the same rules as a witchblade, but specifically mentions being S9?
"Bide your time and hold out hope"
-The Count of Monte Cristo