Fans of Marathon may think they recognize their beloved SPNKR rocket launcher, but as is often the case, looks can be deceiving. As might be expected, the rocket launcher is an extremely specialized weapon. If you're planning on toting it around to harass Grunts with, think again - the rocket launcher was built for anti-vehicular use, and unless you're some sort of demolitions Da Vinci, that's how it'll stay.
Which doesn't mean that they don't come in terrible handy. If you've got a tank or a Banshee glooming down on you, a turret or Hunter breathing your way, its space in your inventory is worth its weight in gold. A solid hit will drop most hunks of metal that are likely to be found, and two or three will almost certainly. A practiced rocket is as good as a well-placed grenade for most groups of enemies, and when you hear a Hunter knocking, a launcher lying around can mean the difference between a ten-minute-long duel that cuts your health in half, and a two-second flight of a missile that dispenses with your problems immediately. A 2x zoom feature adds to its long-range uses.
As with most specialists, however, the launcher has its quirks and its drawbacks. One major problem is that, unless you are very good indeed, it can be VERY hard to actually hit anything - or rather, to hit anything moving, from far enough away that they don't pound you first. If you've ever tried to nail a rocket against a swooping Banshee, twirling and strafing, its warped purple hull filling your crosshairs like so much Wonderglue... well, it's an experience you're not likely to forget. Another problem with the rocket launcher is that, unlike some of the other special-circumstances weapons (the sniper rifle comes to mind), it has very little use except in its particular cases. Take vehicles. Take Hunters. Occasionally, take large groups of enemies - but if you have none of those things, a launcher is absolutely no more than dead weight. You can't stretch it or manipulate it; it's about as versatile as a lead brick. In addition, ammo is scarce, and (as if it really mattered) the melee attack is slower than the U.S. Court of Appeals with a political scandal.
Pros: One of the only (and certainly the simplest) weapon to combat most mounted enemies.
Cons: Difficult to use, ammo hard to come by, usage limited, melee speed disgusting.
Usage: Use it when other methods of fighting vehicles aren't present or feasible. Otherwise, it's wise to shy away.
For: Anybody... in the right circumstances. Some will shun it, saying that there's always another way to kill tanks and such, but there's no denying that it can be a sight for sore eyes when you're glaring down two Banshees, a Wraith, three Ghosts, and enough turrets to boil an ocean.