I've done the full upgrade/update. Only thing I've found that breaks is the login screen for KDE. And that's a quick fix by finding GlassLights-SOHO and moving it to opt/kde/share/apps/kdm/themes
The way to avoid this is to not select (or de-select) KDE-Custom when you do a "full update" (http://www.vectorlinux.com/forum2/index.php?topic=3072.0
). Just thought you might like to know.
@Freeman: I have done the full update several times without any problems except as retired1af has mentioned. The last time I did this I made the above "de-selection" and absolutely had no problems. As for the difference between packages-soho and packages I suspect that there may be certain packages that have been customized/optomized for SOHO or std Gold in the respective repositories.