The Z32 AFM does not have more resolution and it will not measure the airflow more accurately, this is entirely down to the ADC used in the power FC or other
ECU. Theoretically speaking, the lower the maximum measurable airflow, the higher the accuracy of the reading.
You could also increase the maximum measurable airflow on the GC8 sensor by placing it in a bigger pipe, though it would have to be re-scaled.