I have heard that the difference is very small and that the i7 causes the computer to become hotter and uses up more battery life. With very minor differences with the performance. Is this true? If so is it worth it to upgrade to the i7? What would be the point if my computer becomes hotter and battery life is lowered? Just to say "I have an i7"?? Need help before i buy! Thanks THIS QUESTION IS MEANT TOWARDS THE 13" MODEL.