Our organization has thousands of users and well over 150GB of storage used. There isn't an association of storage to performance – they are addressing 2 different elements of the system. We also are running in an Online instance of Dynamics and use both local storage (inside Dynamics) and sharepoint storage in the system. Neither storage types affect performance. From a cost perspective the sharepoint online storage is lower per gigabyte and allows for additional management capabilities vs. the internal Dynamics storage.
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