From experience the PFC can get you beyond 500hp. The problem is as standard the largest airflow reading comes from the Z32 MAF option in the PFC which won't get you there.
With a datlogit or equivalent you can recalibrate the sensors in the PFC. I did this anyway as the standard calibration for the Z32 was out and caused light load issues.
Simple work arounds for the PFC are fit a larger MAF or install the Z32 sensor in a larger pipe and recalibrate your sensor to the map or just remap.
Other ECU's have a MAP sensor that is easier for high boost applications. Unless you're doing the mapping yourself, go with whatever option the person setting up the car recommends as you will get the best outcome.