Thanks for your post,
The two approaches differ in that SQL Server 2008 EE Page and Row Level Compression are applied on an object by object level and SQL Storage Compress compresses at the data file level. The file level approach can be much less complex to implement and manage. In your case SQL 2008 EE is a sunken cost, but for those customers who are not running Enterprise Edition, you would usually find the cost difference vs Enterprise Edition is far greater than the license cost for SQL Storage Compress.
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