I have been using DataFrameworks ClarityNow! for a little while, and I've been pretty impressed. It requires some seriously beefy hardware to keep up with all my datastores (but I've got 10PB of capacity across several different clusters and storage types), but I think it might give you the reporting you want. It also manages to scan and generate results much faster than IIQ, since it doesn't keep historical data.
I have multiple clusters with multiple quota domains with an almost 100% NFS workload.  I'm looking for some management tools that will report on the space utilization within each quota domain - both by directory type and by users if they're defined.  Ideally, I'd then like to be able to group sets of these quota domains into categories - like departments - that I can use for chargeback and forecasting.  Is anybody happy with any of the tools they're running?  Any recommendations? Thanks,    .../Ed
Monitoring space utilization by quota domain