Pretty good. But it could be better. For one, it seems like it was rushed, with somes words using the wrong tensing and just some odds and ends of dialogue that could be improved.
I'll admit, as cool as Kim is, using her in a situation like this doesn't offer as much creativity as the Avatar girls or the Guardians from W.I.T.C.H where they can use powers to gain an advantage. Still, it's nice to see a Kim Possible story.