A tablespace created with the CREATE TEMPORARY TABLESPACE command uses tempfiles instead of datafiles, and as such is often called a "tempfile tablespace". A tempfile tablespace is equivalent to a locally managed datafile tablespace with temporary contents (if that were possible), except that tempfiles do not participate in recovery in anyway and thus do not need to be backed up.

That is, there are no disadvantages to using tempfile temporary tablespaces. It should be standard practice.

I am interested to know what the difference between a tablespace that is "created as temporary" and a "temporary tablespace" is?