The CopyForce feedback I am seeing indicates that most people are taking the default options and trying to copy entire Salesforce instances. No problem...this will work. For production purposes we usually restrict what is copied because quite a few of the tables (like EntitySubscription) are not important for us to backup anyway.
Here is an interesting use case: We wanted Salesforce pricebooks duplicated in our accounting system. CopyForce can do this on one line:
- java -jar CopyForceSqlServer.jar -salesforce production -schema -include Pricebook2,Product2 -sqlserver "...."