I have nothing ESA specific other than, go slowly, don't scan everything all at once until you know how they react to it (within reason of course).

For example, back in the day, I know Nessus was blowing up the gui on our Brocade switches, they'd pass traffic, but couldn't be configed until a reboot...   This taught us caution... do one, then check it all out before you scan all of them....