Hello,

You will have to use the REUSE STORAGE if :

- You have to delete all records of a table in order to insert new records (same volume)... I think that SQL*LOADER use that when you opt for the option TRUNCATE in ctl file.

- You have to drop a very big table. You start by TRUNCATE command with REUSE STORAGE, then, when you have free ressources (in the night for example), you will use :
ALTER TABLE table_name deallocate unused keep xxxxM;
...
ALTER TABLE table_name deallocate unused keep xxxxM;
every time you deallocate some space without consuming all the available ressource...

Hope this helps