I know there's tons of these, but I need help from the pros. I am about to purchase my first Mac at best buy with the 18 month financing. I have ruled out the new iMacs (as awesome as they are) because I could really use a new laptop for school. I am wondering if it is justifiable to get the 15" retina MacBook Pro? I want to start blogging and editing photos and videos. I am more than willing to purchase a USB external drive.