If I'm not mistaken, it's alloy wheels, power locks/windows and ac, plus it opens up packages you can't otherwise get. That being said, I think if you add the half doors, you get power locks and windows on a sport... If you don't want the half doors, you could likely easily sell them.The jump from the Sport to the Sport S is $4k. On Jeep's website it's hard to see what the difference in options is. What are you getting for the $4k?