I have yet to get a dump as I am using the OE dump which contains a cat.
I run the Kakimoto front pipe which deletes the standard cat(s).
When I get the dump done, I will either have a Metal Cat welded into my Kakimoto pipe or I will sell the front pipe and get a dump/frontpipe/cat combo.
If I didn't live in Vic, where the police are defect-happy, I would just put a 3.25" dump on and be done with it