As usual, after I finished the work, I got a couple more ideas for tightening it up. One big improvement to the process would be to use the lookup tab on the Data Driven Query task to check the imported line against the contents of the table. This would change the total refresh into a differential one, where the lookup would import the row only if it did not exist in the check register table.

Lookups are not without their own limitations, however. The biggest of which is the extra time they take to run, since they don't work by sets but by a row at a time. Testing would establish its applicability. If the number of changes were small, it may improve execution speed, but if many changes occurred, it would be best to manage them in a set-based solution.

Finally, I would like to thank my colleague, Sesha Chivakula, for her help in creating this solution.