it is about 35 - 40 minutes from hwy 192 Disneys main gate to The main intersection in Poinciana (marigold and cypress parkway), however keep in mind areas of Poinciana like village 7 are upto 15 minutes away from the center of Poinciana. The best vacation home areas near disney are in Hwy 27 and east 192.
It depends on time of day, traffic, etc. There are several schools along the road to Poinciana which could tie up traffic, I usually allow myself an hour each way to get to the 34759 area. Part of Poinciana Blvd is 2 lane which ties up traffic more. If you are coming from Magic Kingdom, it could be longer as it is the furthest park. If you need help in choosing a location, please feel free to call.
From where Poinciana Blvd meets Pleasant Hill Rd. you are looking at a minimum of 20 miles or so to Disney with Magic Kingdom being the furthest park. The speed limit is not 60mph. 20 or 25 minutes is not realistic. I would personally allow 40-50 minutes to get to your destination, but the actual drive time could be less as suggested below and depending on where exactly you are coming from and headed to, the route you take, time of day, etc.
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if you work at Disney then you will probably have a 45 - 50 min commute each way each day depending on the time of year and traffic