Short answer: We have not turned on FRBR (Functional Requirements for Bibliographic Records) because of issues with retrieval after testing. FRBR is an attempt to group versions together.
While it is used by some PASCAL libraries, it doesn't work well for us.
Clemson University Libraries, Charleston Southern University Library and The Citadel have enabled it.
Unfortunately, turning on deduping messes with our retrieval, heavily impacted are the results from special collections. Having deduping on combines information from records (using one as the preferred) when our users will care about specific details that make the items different.
If you are really interested and want to learn more about the process, read on: Dedup and FRBR Processes in Primo VE (Ex Libris Knowledge Center)