I experinced that on my test bed i cannot
# mount /dev/gvinum/<myraid> /mnt
mount: /dev/gvinum/<myraid> on /mnt: incorrect super block
But it read the old config fine it looks like
Soeren Straarup | aka OZ2DAK aka Xride
FreeBSD wannabe | FreeBSD since 2.2.6-R
If you see the light at the end of the tunnel,
then make sure it is not a train..