I'd say never.
they cost almost as much as a 10 man squad, I'd almost always rather have 10 extra bodies.
He also forces the unit to take extra wounds if they fail combat. Why not let me fall back and hope they make an iron D roll. Or if they are wiped...who cares do we really expect most guard units to last multiple turns in combat vs anything ment to be scary in combat?
Even without iron D your spending 50+ points to improve the leadership of a unit worth....just over 50 points. why not just take another unit? more fire power, more wounds and well even if you fail aleadership test who cares you still have the other unit. i mean oo 1 mor epoint of leader ship...
that without counting the fact they kill your own officers/troops.
If you really want, use a special character or somethng from another codex. they are far better.
For example a cannones with a book of st lucious takes what? 55 points but you get a better unit in power armour. can join any unit with out needing some special rule and affects everything within 6". Has leader ship 10 that will never be modified so your conscripts will nver suffer an effective leadership 5 after lossing combat then taking wounds because they "auto passed".
I love the idea behind them but man they are expensive. also some people but em in lots of squads because without independent commisars doctren you have to... so for every 3 commisars you can get a leman russ. for 2 you could get a hell hound....
I can't see them ever being viable. Even at 10 points i would question them.
Last edited by Morgal; 12-12-08 at 02:54 PM.