What are some alternatives?
When comparing Vector Artist and Gromit-MPX, you can also consider the following products
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Epic Pen - A windows tool for drawing over your desktop and applications
SVG Cleaner - Generally, SVG files produced by vector editors contain a lot of unused elements and attributes...
FlySketch - FlySketch from Flying allows you to draw on top of any program which can't draw itself.
Scour - SVG Optimizer / Cleaner
Ardesia - Ardesia is an usefull software for use your desktop as a Sketchpad.