It depends on how you configure the speed of the fans. The rated airflow (in CFM) of each fan is dependent on the speed at which the fans are set to spin (in percentage).
The AER RGB 120mm is rated at max. 1500rpm that will produce 52CFM of air. On the other hand, the AER P 120mm is rated at max. 2000rpm that will produce 73CFM of air.
If you were, say, install the two AER RGB fans as exhaust and two AER P fans as intakes, all set to spin at their max. speeds, then, you will exhaust 52CFM + 52CFM = 104CFM of air (with AER RGB spinning at 1500rpm) and you will intake 73CFM + 73CFM = 146CFM of air (with AER P spinning at 2000rpm). This is ideal as more air are going in than going out (positive airflow).
But, if say, you find the AER P too loud and configure it to run at 50% (i.e., 1000rpm), then, the approx. corresponding CFM will be 50% of 73CFM which is only 36.5CFM each. This will result in negative airflow if you don't adjust the speed of the exhaust to a certain percentage that will produce a lower CFM than the intakes.
So, the positive or negative airflow can be obtained depending on how fast you run the individual fans themselves (whatever the max. ratings the fan has on its specs).
On another note, regarding the AER RGB fans:
Though both AER P (non-RGB) and AER RGB can be plugged directly to the motherboard's fan headers for the fans to spin, the RGB version requires the NZXT HUE+ controller for you to enable and control the lighting (http://www.nzxt.com/products/aer-rgb-hue).
Though you can use the AER RGB without the HUE+, it defeats the purpose of getting the RGB version. So, for the two AER RGB you will get, (which are both 4-pin PWM fans), the fans are plugged into the HUE+ controller (with both fans can be linked) and as such will only use up one PWM fan header of your motherboard (as opposed to two). The HUE+ controller itself is then powered via a DC adapter (Molex directly to the PSU) and communicates with the motherboard/CAM software via an available USB2.0 9-pin header (http://blog.nzxt.com/2016/10/how-to-install-nzxt-aer-rgb-fans/).
So, with this setup (AER RGB with HUE+ at intakes and AER P at exhausts), you will only be using 4 out of the 5 fan headers of your motherboard. Here's a sample configuration:
CPU_FAN (in PWM-mode) <---- Your CPU Cooler
CPU_OPT (in PWM-mode) <---- Top Exhaust AER P PWM fan (it's the header nearest to the top)
AIO_PUMP (in PWM-mode) <---- Rear Exhaust AER P PWM fan (its' the header nearest to the rear)
CHA_FAN1 (in PWM-mode) <---- Linked two AER RGB PWM fans at front intake (connected to the HUE+ controller)
CHA_FAN2 <---- not used (available)
USB2.0 (9-pin) header <---- HUE+ controller (for data communication)
PSU's Molex connector <---- HUE+ controller (for power)