Yes, you can save your Excel data as CSV files, then you can import them to Quicklist. Most data management applications let you save to CSV files, so practically QuickList can handle files from any popular source.

QuickList lets you import and operate on maximum 2 lists at a time. If you need to handle more lists, you can simply work with them 2 at a time. For example, if you need to obtain a list of items that can be found in all your 3 lists, you can intersect list A with list B, save the output, then interest the output with list C.

You can use the “Difference” function: import your mailing list as Source A, then import your unsubscribed list as Source B, then perform a difference operation, A – B. The output will contain only those contacts that are found in your mailing list but NOT in your unsubscribed list.

First of all, you need to make sure that the option “automatically eliminate duplicated source fields” is enabled. You can find this option in the Options -> Settings window. Then simply open open the list with QuickList and the program will import & show your list without duplicated fields. Then you can save your cleaned list back to a CSV file.

The latest QuickList version is 1.1.8. You can always check for updates by using the updates button available from your main QuickList toolbar.