You are wrong on several points. Both cameron and Brown have got in Obama people to advise them.
Unlike the American debates, our three can be seen debating each other every week at PMQs and each is well know to the public. The American debates are usually the first time the candidates have met and debated with each other, so it is more revealing.
Unlike a Presidential election, we are voting for a party, not a Party leader. We may elect a dimwit, but the party machine will compensate for that.