They are very unorganized, it doesn't matter if one has a rocket launcher (which I have never seen), if you got 3 CW Raiders (by the way I have never seen more then 3 raiders at once in Fallout 3), VS the 5 or 6 Powder Gangers that were in Goodsprings, its obvious the Powder Gangers would win, besides the CW Raiders seem to run away most of the time.
Have you been to Evergreen Mills? They managed to capture a behemouth and there's a freaking fat man in there. . .
CW raiders also use mines (Rock salt's lair), flamers, explosive collars, and combined defensive nests of turrets and missile launchers (extreme south - bridge near the library as an example). I remember running into one with a mini-gun as well, though he could have scavenged that from a dead mutant or BoS knight.
NV Fiends (Jackals and Vipers were a joke) have energy weapons but they always seem to be of poor quality (bosses excluded). I do not remember them ever using mines or a turret. . .though I didn't probe deeply into Vault 3.
I'd give the Fiends a slight edge if the battle occurred out in the open, but the CW raiders have more tactical defensive positions and would probably slaughter them if they were defending. (very nerdish, I know).