Considerations for Single vs. Multiple Item Master Organizations in a Shared Fusion Environment

Summary:

Both companies are using the same Fusion environment, and two separate ledgers have been defined for each company. Additionally, the LEs and BUs linked to these ledgers are independent.
In this environment, we think that the Item Master Organization (IMO) associated with each BU should also be defined separately for each company and operated as Multiple IMOs. However, Oracle ERP generally recommends using a Single IMO, so we would like to hear your opinions.
We are using PO, but there will never be transactions in the future where the same item is used across companies, as they operate completely independent businesses.