Hi EricNichols,
VMware's solution is writable volumes, either with/without UEM for managing the OST location. Roaming the OST with UEM natively is NOT recommended (!!).
If you don't want to use App Volumes (writables), FSLogix is another option. FSLogix has been acquired by Microsoft and I personally wouldn't be surprised if this becomes a standard services/feature in future Windows builds. FSLogix also has an option for concurrent container use, as far as I know. Containers can be used for both Office 365 and Windows Search.
\\ Ivan
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