I thought this is a good write up on why air burst rounds are
useful.
http://www.navytimes.com/news/2007/06/dn_munitionstest_070615/
Currently, only the 40mm AGLs eg on Bionix 40/50s have air burst
capability.
http://www.stengg.com/upload/990Mjmg5MNKCJeWnLRj.pdf
With the new Bionix 2 mounting the 30mm Mk 44 Bushmaster 2 guns,
this will provide a significantly improved anti-infantry
capability. This will also partly explain why SAF went for the
Bionix 2.
Potential enemy - don't bother with foxholes and shellscrapes
from now on...