I agree with the fact that the Ultimax flaw lies in it being
either box fed or 100-rounds drum fed.Belt-fed weapons though can
hold easily like 200 rounds,but it may be entangled with the
vegetation or may get caught by fixtures when the SAW gunner is
doing FIBUA.Besides,a drum mag though difficult to reload does have
its advantages in the sense that I would say it is almost tangle
free,and that it will take a lesser time to reload the weapon
compared with using belt-fed ammunition,which seems to be more
cumbersome during the reloading phase.
However,just to side-track alittle,there are C-mags for M16
right?But does the SAF use those?And if used,who will be using
them?The normal riflemen or the SAW gunner who will then be armed
with an M16?Although I do agree that the SAF SAW gunners usually
use the standard M16 box magazine, but doesn't it defeat the
purpose as the SAW gunners will zap out the entire magazine of
round in a blink of an eye.
However,we must bear in mind that,in the platoon level
operations,there is a GPMG support team which uses the FN MAG GMPG
which fires from belts of 7.62mm ammunition.And if the GPMG is
fitted with a bipod,it makes the weapon more mobile and provides
more firepower due to its calibre and higher rate of fire.Thus,the
need for a belt-fed SAW in the section level is removed due to the
availability of the GPMG which is belt-fed to provide additional
firepower.
But surely,SAF will have a small amount of most types of weapons in
the world for our Spec Ops forces to operate with.If the need is
there,perhaps the SAF could consider a weapon along the lines of
the IDF Negev or FN M249 Minimi,both are belt-fed and combat
proven. 
