Open source programs can be very good or ... not so good. But it's free. So there's not much point in complaining.
This one so far is quite good. I read complaints that Inkscape can be slow and I imagine with larger projects this may be true but, so far. It seems to work quite well. The interface is easy to understand and the program seems to work well.
In just about an hour of tutorials I was able to reproduce this old image I drew in Flash some 10 years ago using Inkscape.
The new image is an SVG so, that's cool.
Old using Flash
New using Inkscape