There's some problems with gaps in the coloring if you disable the precinct/block group lines.
On the other hand, the sharing function is nice.
There doesn't seem to be a function for positioning or editing the district labels just yet. The latter is a nicety, but the former is a necessity if you have U-shaped district.
Here's a quick and dirty Congressional map made using some non-partisan heuristics based on county size with the seven largest counties being the staring points.
http://dra.indirect.cc/join/55db0c2b-dddc-4f41-882d-15b5519a6034Clyburn probably wouldn't be happy with my map as he conceivably could suffer a primary challenge if he messes up, but the Richland-based district is safe D and the Horry- and Charleston-based districts are swing districts that the Dems might have won both this year.
