If you put two fans at the top, the use of the dust filter at the top will be moot/restrictive. If anything it also allows the space that isn't filtered to have dust enter the chassis. I'd say leave the top fans mounting locations alone and have the case to set up to have the air intake from the front and exhaust through the rear.
About the case, the airflow is improved compared to the P series since it shares the same design but it's airflow is lackluster compared to other front vented panel design cases like the CoolerMaster H500M or the Fractal Design Meshify C.
Where are you located and what sort of case options do you have at your disposal? We'll also need to know what the specs to your build will be that goes into said chassis.
List specs like so:
CPU:
CPU Cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU: