SharePoint/Salesforce Integration

Hello folks --    We currently use both Salesforce and SharePoint to save and share important client docs.     Biggest challenges facing our teams now:

• Salesforce files are hard to sort. A client record could have between 10-25 associated with it and we can only sort by name or date uploaded. We've tried naming conventions but user adoption has been tough.
• Storage limits within Salesforce, storing this stuff there can get pricey.
• Redundancy, users are hesitant to bounce between systems to upload all these docs. 

  I see there are a number of options on the AppExchange at a variety of features and price points.    

• If you've used one of these products in the past, how did you like it? 
• Any gotchas or or surprises you wish you had know about going in?
• Do you consider the tool a good value when comparing the price vs features?

Thanks!