If there are vehicles that need to be destroyed or immobilized, there are dedicated anti-vehicular weapons available. Same with helicopters. A precision weapon such as this is not a first resort for shooting down a helicopter. It's something you'd use if you had no other weapon. And I highly doubt that any M'sian, S'porean or Indonesian unit will find itself with just this weapon to down a helo or take out an APC.
Given the terrain of SE Asia, I am very skeptical as to usefulness of the weapon since one of its main advantages is its range. That's negated by the large amounts of jungle or urbanized areas in Malaysia, Singapore and Indonesia.
I will grant that Special Forces may be able make use of this (in place of man portable missile systems) but if its only useful to special forces, then it is a weapon that is extremely limited in its use.
As far as I know, the largest calibre weapon in use by the SAF is the .338 and that's not really a powerful anti-materiel round when compared to the 12.7. It just seems, to me, to be a case of "my bullet is bigger than yours." For all practical purposes, there are very few areas in which this weapon can be deployed to make use of its range.