Spears spits back at K Fed

Britney Spears is facing a heated battle with her ex-husband, Kevin Federline, for custody of their young sons. Allegations have been flying from both sides about each other's suitability as parents. In a recent twist the singer has reportedly recorded a song criticising Kevin. Do you think Britney's a fit parent or is Kevin exploiting her recent difficulties for his own benefit? Whose side are you on? Have your say.