At least for South Carolina, which is not on the township range system,
if you are platting more than a handful of deeds in a particular area,
the maps are essential. Make sure you get the version that at a
minimum has watercourses, because they are the most helpful feature in
terms of placing a plat . Roads and political boundaries change at lot.
One minor problem with the version available from Deedmapper is that it
does not show all watercourses that are reflected on current
topographical maps--smaller branches are left out in some areas. I have
begun highlighting streams in the topographical maps (7.5 minute
series) and using them for comparative purposes with the Deedmapper
versions. They are essentially at the same scale.