We store everything in there from Advertising Records, to accounting records, contracts, billing invoices, all types of HR documents.  We even have a drive setup for WORM-type records which can never be edited once they are inserted in there.  Things like HR records are perfect candidates because you can batten down who  can see them, we even have company reps that can see HR folders, but none of the documents in the other companies folders, which is good because we have several other companies.  Contracts are setup in company subfolders so that only company employees with the need to know can see the agreements for that particular company, etc.  Security shouldn't be your only concern, you should think about what types of automation you may need going forward.  For instance, putting our billing invoice company folders into Laserfiche allowed us to setup a workflow that routes thousands upon thousands of billing invoices into their respective company subfolders via workflow.  Users just dump them all into one routing folder, and workflow picks them off and starts routing them, attaching metadata as it goes. 

Rick