The route with the fewest tolls is to take the North exit from the airport to 528 west to I-4 west.
My preferred route at any time of day is the South exit from the airport to 417 south to 536 which turns into Epcot Center Drive once on WDW property.
417 is the safest. especially at night you will drive through two $1.00 tolls.
Will you elaborate on safest?
As PhotoDave alluded to, Route 528 and I-4 (which you must drive on when using the North Exit from MCO) tends to have a lot of speed-demons on it. The South Exit's Route 417 is a lot more typical highway traffic.
-Rob
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