Re: Predators vs. COBRAs
1. Probably not. Cobra have no armor (unless they wear some, but that doesn't work well for guerillas.) But they can take much more damage than you would expect, and get back up. (In the second book, a cobra is shot (by a shotgun as I recall) at point blank range and stunned, but the enemy assumes that he is dead. He gets up in the "morgue" and breaks out.)
2. Usually very, very good, they have enhanced senses and are trained for guerilla war.
3. Cobras have 3 lasers, two low power but lethal to unarmored targets, one very powerful (an "anti-vehicle" laser); plus several sonic weapons and a short ranged but very powerful "arc-thrower" which shorts out electronics as well as hitting like a lightening bolt.
Cobras are also very strong (they have their major bones reinforced to be unbreakable), so strong that if they do not lift heavy objects correctly they can injure their soft body tissues. A cobra could lift a predator one handed and throw him 10 or 15 meters easily. Cobras are also VERY fast, the viewpoint character in the first book describes when he first sees a cobra move it was a blur, his eyes couldn't see the details.