It's easier to keep on top of cleaning the EGR on the Z19DTH. I had one in my old Vectra, and just used to take it off, and clean it every 6 months. You can also get a different gasket which reduces the amount of EG coming back into the inlet to the minimum amount the ECU needs before throwing the EML on.
Not sure if Matt has discontinued them or if they're just out of stock. Without stepping on his toes or offending him then if you need one that quickly then try here.
If he can still get them I would suggest asking him, do you need the cheater too to go with that. If he isn't doing them then maybe this will help.