I agree with Armin...
Better to use two "Prefix" qualifiers to identify tables for intended purposes, THEN tack on a SYS() call for generic purposes.

Another alternative is to use
CREATE CURSOR
instead of
CREATE TABLE...

This way VFP automatically control internal temp file names and uniqueness. You can still INDEX ON, APPEND, etc and work with your arrays as needed, then when they are closed, they are also destroyed...