Thanks for the reply. That helps a lot. The way the program works is that I pay X dollars up front, and then monthly payments of $335/month. That $335/month covers gas, car washes, insurance, maintenance, brakes, tires, everything. So, to answer your question, no, I don't have to pay for gas. If the car gets 20 mpg or 10 mpg, it makes no difference to me because I pay the same amount.
The nimbleness is the thing that attracts me to the Edge over the Explorer. My daily commute is 65 miles round trip and it's all highway miles. My concern with the Explorer is that it might not be so great on the highway (at least not compared to the Edge). Have you had the chance to drive the Edge on the highway? If so, how does it compare to your 2006 Explorer?