Bryant,
From experience, the car services are sometimes better than a taxi. I have taken a taxi from a park to my resort twice at Disney (running late for dinner reservations) and both times it came out to be more than a pre-scheduled amount with Mears. I have also taken a car service off property. I planned ahead of time with the driver that brought us from airport. He gave us a card and told us to just give him a call ahead of time and he would schedule us in. You can call Mears and ask them to set you up a time and ask them in that conversation if you can contact them earlier or later to adjust your pick up time. They are pretty good about accomodating guests. Have you contacted Quicksilver on the boards here. They are a great car service company and extremely reliable. Check out their rates also. In the end, I would say plan for the car service over the taxis. My experiences with taxis have all been, they say it won't be more than a certain price, but they always seem to make it jump twice what they said it would be. Unless you can get a taxi driver to agree on a set price before you leave, but that is hard to do. If you choose a taxi, make sure it is a yellow checker cab. They have tons of non-regulated taxis that will pirate you that come through the property.
