Personally, I have vowed NEVER to use Swarm. They are a cheap way to win in my opinion. When your enemy has 'em, you can't drop mines, fire missiles, and especially not torpedoes! The only way to fight is to kill them REALLY fast with ONLY your energy weapons, before they get blown off by the sheer number of missiles.
I've always found Swarm very, very bad weapons. And unbalanced. I keep with original ships and (mostly) weapons because I know I can beat almost anyone with it unless they have new ships/weapons, like Swarm Missiles.
Generally I go with one missile, Tizona, 4x other, a Nova(NOT for Dogfighting) and a screamer mine(or a ripper, can't remember which).
I've used the Super nova mine in a DF, I killed him instantly. I was simply thrusting when he was 250m behind and dropped two. Instant death.
Personally, the Swarm should be REMOVED. And supernova reduced slightly. It *IS* unbalanced. I've been beaten PURELY because they used ONLY swarm. NOT supposed to happen. And now that I'm thinking of this, I'm putting it in the Wiki as my opinion on changes....