The standard Anti-Missile System (AMS)
destroys 1 to 6 missiles, but expends 2-12 shots in the process.
Since it only has 12 shots per ton of ammunition, it can go through a
ton or two of ammo very quickly. It shoots down enough missiles to
destroy an entire SRM flight, but not enough to disrupt an LRM
salvo. To be a worthwhile investment, the AMS needs at least 2
tons of ammunition; that makes it a 2.5 ton system. Unless your
'Mech already has maximum armor, it would be better to devote
this tonnage to additional armor. The AMS is a good defensive
weapon, but it is not good enough to warrant wide-spread use.
The Laser AMS shoots down twice as many
missiles as the standard AMS and doesn't require ammunition. It
does, however, build up 3 to 18 point of heat each time it fires,
making it very hard to control heat build-up. The Laser AMS is
effective against both SRMs and LRMs and is a good defensive
system for Support or Assault 'Mechs. If you use it, make sure you
have enough heat sinks to deal with the 11-13 points of heat it will
build up on average. Carrying a Coolant System would eliminate much of the risk of sudden heat
build-up.