If RedGate Data Compare is used against relatively small amount of reference data, then it works just fine. The problem is that they generate data scripts that are RBAR on steroids in the form of INSERT/VALUES for each row. If you have a lot of data, then you should consider exporting the data to a "native" file and bulk inserting it when you get it to your destination. If the editions or releases of SQL Server are different, you may have to settle for delimited files, instead, but will still be much faster than 1 INSERT/VALUES per row for a million rows AND it will won't take as much room on your distribution media.