Why do you think you cannot construct a CHECK CONSTRAINT on a table column using GetDate()?
ALTER TABLE yourtable ADD CONSTRAINT CK_col CHECK (yourcol <= GetDate())
will create such a constraint.
I doubt there is any performance difference between a RULE and a CONSTRAINT. There is nothing preventing you from using a RULE, it's just that the CONSTRAINT syntax is SQL Standard and the RULE is not.
Custom Apps, Inc.