My 2 Cents since that's about all it's worth ;)

We use Legato Cluster to Cluster 2 SQL Server machines using the Netapps Box.
I currently have them in Active/Passive.
It works great when one server fails the other server takes over.
The only caveat w/ the filer is I have to run a RSH script before SQL Server starts to release the lock from the downed machine.

Fail over typically takes about a minute.

Joshua Morgan
PH: (864) 331-7939
jmorgan@trivergent.com