Re: The difference
!Draw -> ArtWorks -> Xara Xtreme -> Inkscape
Yeah, !Draw and ArtWorks didn't share code, but ArtWorks was a natural evolution to a !Draw user.
And Inkscape code isn't related to Xara, but the UI is heavily inspired by it.
You might find Inkscape quickly becomes home, filling the whole left by !Draw. I did. :-)