The cheeseburger is one of the most intelligently designed sandwiches ever made. Think about it; it has meat, it has dairy, it has grains. That's three of the five major food groups in one hand held meal, and if you add a side of fries you've eaten your vegetables, too.
Now, those in the nutrition world will try to dissuade you by focusing on the negative elements such as "saturated fats" and "cholesterol" but I believe those to be made up words the pharmaceutical industry has created to sell more drugs. My doctor confirmed this for me last fall as he wrote me my first prescription for a simvastatin after I concluded my first round of burger reviews.