Currently we are using XE SP 17 with Update 3. We are considering applying Update 6 or 7. Has anybody installed or thought of installing either update and what were the results?
I have installed XU7 a number of times recently. Both XU6 and XU7 have issues - but none too severe to prevent a successful update. I would go with the latest -- XU7 - since it has more functionality changes that XU6.
You should consider moving off SP17 first however, since that service pack was notorious. You probably also have to install the planner ESU as well.