Hi Rob,
You can bind cross tab reports from your WebI reports into Xcelsius using an integration tool called
Xcelsius Web Intelligence Intregration Suite.
This will give you the full functionality of Web Intelligence inside an Xcelsius dashboard- drill-down, cross tabs, even an ad hoc query panel, all bound into the Xcelsius interface.
This would remove the need to use QaaWs or Live Office, so you can probably realize some performance gains and handle larger data volumes.
Cheers,
Andrew