Yep, swarms are often a great addition to your forces.
I do have some reservations about jungle swarms though and my concerns are about the cost (not because I'm a cheap skate with deep pockets !), the points cost.
When I first paid attention to the jungle swarm points value I was suprised they were 60 pts. It seemed a lot to me.
Let's do a comparison to help me make my point.
Tomb Swarm
The same profile except a lower movement of 4 rather than the jungle swarm's move of 5. In addition, Tomb Swarms benefit from the 'it came from below' special rule. This can be used if the player chooses and provides extra flexibility during deployment
Rat Swarm
Again, the same profile except ratties can move an extra inch (ie 6 inches rather than 5). Rattie swarms are also expendable (special Skaven rule) so don't cause panic if they get squished. (Big rats simply don't give a tossed piece of moldy edam for their lesser brethren)
So, what does that tell us ? Not a lot until you see this...
Tomb Swarm 45pts
Rat Swarm 45pts
Jungle Swarm 60pts (?!)
Rat Swarm 45pts
Jungle Swarm 60pts (?!)
This is why I cannot unreservedly recommend the use of Jungies.
Right, having said all that I should say that all swarms do remain great additions to your army. They are 'unbreakable' (for unbreakable you can read 'indisposable' or 'almost pricelss' if you like)
Unbreakable is such a tactical benefit that it's difficult to leave any of these types of troops at home - in their aquariun in the case of jungies :)
In a 2000pt game I would probably still take at least 2 bases of Jungle Swarms in 1 unit (you can only have 1 unit of any type of swarm, for all armies. Yes, they're that useful !)
Don't underestimate the ability to hold up a key enemy unit and flank them and fire over the top of your swarm too !
Take this awesome fantasy unit but know that you're being a bit ripped off so don't take too many !