Kra'Vak Roles

Yesterday in a discussion about the battles at the GZG 
West(East?) Coast Con, Oerjan Ohlson mentioned that Kra'Vak 
cannot seriously compete head on with a human enemy. After 
closer scrutinization, it looks like that is pretty accurate. Initially
I 
compared sizes, not points costs, and that's where I made my 
initial error.

The question is, what IS the combat role of the Kra'Vak. How are 
they best utilised, if not head-on, where their limited arc K-Guns 
are most likely to get the successful targetting?

I've noticed that defensive systems seem to matter naught against 
them (Screens ignored and Armour all but ignored), I'm just curious 
as to how they might be played best. I'd also like to know some 
tips on how to beat them, as one member of my group is thinking 
of playing them, and they seem to be almost built to screw over my 
army of choice, FSE. What's the best way to contend with 
ScatterPacks for my Salvo Missiles?

Morgan Vening