They all suck, and emit crap gigantic SVG files.
Here is the way to do it that make perfectly covering SVG files that don't suck.
gs -dBATCH -dSAFER -dNOPAUSE \
-sDEVICE=svg \
-sOutputFile=Logo.svg Logo.pdf
If you have an Adobe Illustrator AI file instead of a PDF file, just put a PDF filename extension on the end, it will work fine.