This is one of the newest missiles in the GTVA tactical arsenal. It boasts a fast-locking "fuzzy logic" guidance computer, a powerful thruster, and high agility. The end result is a missile that space superiority squadrons will most certainly be seeing a lot of during their career.
In addition to the obvious advantage of intercept ability, the Harpoon is also a quite compact weapon. The Myrmidon fighter, for example, can carry 32 of these warheads. With its powerful explosive, two simultaneous missiles hits is generally considered a kill on anything but the heaviest assault fighters, or bombers.
The Harpoon is tough to beat in terms of payoff per time invested and payload space. Unless your mission goals require you to fill your banks with other ordnance, a launcher full of these can almost always be put to good use.