Yeah, it means the same thing. IVA (Intake Valve Actuator) and VVA (Variable Valve Actuator), same crap. MXS and NXS changed to a common actuator housing that have the valve actuators and engine brakes in 1 housing for 2 cylinders (3 total).
I have the 625HP turbos and deleted actuators on a 2005 MXS, absolutely zero problems with anything on the engine. only about 50k miles but love it. Its still de-tuned for the break-in period but going to 900HP and 3200 pounds of torque approximately at the wheels. People talk trash about the Acert all the time but it is by far the greatest engine I've ever had.