IN, EXISTS or ANY?

Folks,

I was wondering if there is any difference in execution speed for the
following three statements:

WHERE case_id IN (SELECT case_id FROM case_clients
		     WHERE matter_no = '123.122342');
or:

WHERE case_id = ANY (SELECT case_id FROM case_clients
		     WHERE matter_no = '123.122342');
or

WHERE EXISTS ( SELECT case_id FROM case_clients
		     WHERE matter_no = '123.122342'
		     AND case_id = cases.case_id);

... or does the parser handle all three exactly the same way?

-Josh Berkus