I posted this in Charlotte, but will try to help here:
a. From Bax to the Tyvola exit is 10 miles.... In Rush Hour without a wreck at Carowinds, it will take about 15 min, maybe a little less. From Tyvola to Southpark is another 3 or so miles, because of traffic and lights, it could take you another 10 min or so, maybe a few min more or less...
b. Taxes are cheaper in general in SC. Use the search button at the top and search for SC taxes, there are tons of information there that could help.
c. The schools are very good and highly rated, the current schools assignments are: Elem; Orchard Park. Middle; Gold Hill... but is slated to change in 2011 to the new Banks St middle. High; Fort Mill High School. The elem school is located in Baxter.
Orchard Park Elementary School - Homepage
Welcome to Baxter Village | Fort Mill SC Master Planned Community
Traffic can be very heaving traveling from SC to NC with the backups starting at 485 and crawling to uptown. If there is an accident, it can back up into SC... another merging trouble spot is always Carowinds... On average the traffic is heavy but it moves, about once every week or so there can be a wreck that backs everything up....
Not really heavy coming into SC only thru traffic for the most part. The heavy 77 south traffic is coming from the north areas feeding into Charlotte.