This one is about the only one that I have any experience with.  Import and Export both make a mess of things.  I created an issue on launchpad a month or so back concerning my findings.  If there are any specific questions, I think my Dad is better qualified to answer them than me, as he's done most of the conversion from SVG to XAML for his WaterSums software's switch from Adobe SVG Viewer to Silverlight.  While Inkscape's XAML export was a good start, it needed quite a bit of cleaning up and similar before it would work.