Is the FireEye app compatible with ESS?
I have both deployed but there is some overlap between the TA-FireEye that comes with ESS and the FireEye app in splunkbase
It looks to me that the only thing missing from the FireEye app are the tags but I'd appreciate a second opinion
No, it is not, because the TA is hopelessly borked; see here:
They're expected not to conflict, but they serve different purposes. The TA models FireEye data to the common information model, which is necessary for using it in ES or pivoting in data models. The FireEye app is more about quick visualization of FireEye specific metrics, very useful for understanding what data is being gathered in a more specific context.
Actually, it doesn't (not really). See here:
https://answers.splunk.com/answers/711184/did-you-fix-the-fireeye-tas-eventtypesconf-if-so-p.html?mi...