Good points. It is the only ranged weapon that can make a disarm attack (as disarm normally requires a melee attack, with an AoO). However, it is a risky move to try a disarm because if you lose, the defender gets to try and disarm the attacker. Not only will that defender(with, say, a longsword) have a +2 on the first opposed attack rolls, she will get that +2 on their immediate attempt to disarm you. On top of that, you probably used your movement that round to get into position leaving yourself unarmed when that original defender attempts to stab you with a longsword when her turn comes around. I think I will stick with the trip to at least slow her down as she is chasing me after the front lines have been beat down.
Too bad I couldn't do 1d2 points of subdual on the back of her hand to make her drop that weapon, as long as she wasn't wearing any armor. Now that would be cooler.