Nike_7688
So was replacing the hybrid stock fans with ML Pro's a visual choice or for performance? Did you test both? I'm curious what your thoughts are.

Ciddharthas
One thing to keep in mind:
 
Yes, your radiator will get better airflow without a dust filter, but if you don't use one, not only will you allow dust into your pc, but it will clog up the radiator itself too.  So even if you get better temps right now when not using a filter, eventually they will get worse as the radiator gets clogged up.  You can clean a radiator pretty easily, but getting it out of the case and back in can be a pain.
 
There is also a sort of "sweet spot" where dust filters are concerned, between allowing too much airflow (and therefore dust) through and allowing too little (which will catch more dust but will constrict the airflow too much).  Some cases go overkill on dust filters/mesh, and some don't have enough.  Not sure where yours falls with respect to that.

pbalogh

Ciddharthas
One thing to keep in mind:
 
Yes, your radiator will get better airflow without a dust filter, but if you don't use one, not only will you allow dust into your pc, but it will clog up the radiator itself too.  So even if you get better temps right now when not using a filter, eventually they will get worse as the radiator gets clogged up.  You can clean a radiator pretty easily, but getting it out of the case and back in can be a pain.
 
There is also a sort of "sweet spot" where dust filters are concerned, between allowing too much airflow (and therefore dust) through and allowing too little (which will catch more dust but will constrict the airflow too much).  Some cases go overkill on dust filters/mesh, and some don't have enough.  Not sure where yours falls with respect to that.

This would completely depend on whether your case has positive pressure (ie higher pressure inside = blow out dust) or negative pressure (lower pressure inside, sucks in dust). Will depend on your fan configuration as well as how airtight your case is....

HeavyHemi

Ciddharthas

pbalogh

Ciddharthas
One thing to keep in mind:
 
Yes, your radiator will get better airflow without a dust filter, but if you don't use one, not only will you allow dust into your pc, but it will clog up the radiator itself too.  So even if you get better temps right now when not using a filter, eventually they will get worse as the radiator gets clogged up.  You can clean a radiator pretty easily, but getting it out of the case and back in can be a pain.
 
There is also a sort of "sweet spot" where dust filters are concerned, between allowing too much airflow (and therefore dust) through and allowing too little (which will catch more dust but will constrict the airflow too much).  Some cases go overkill on dust filters/mesh, and some don't have enough.  Not sure where yours falls with respect to that.

This would completely depend on whether your case has positive pressure (ie higher pressure inside = blow out dust) or negative pressure (lower pressure inside, sucks in dust). Will depend on your fan configuration as well as how airtight your case is....

Positive/negative pressure only affects whether you have dust coming into your pc through holes that don't have fans in them.  If a fan is blowing air into your computer, it's going to be blowing dust too.  That dust will get caught by filters, by the radiator, or will get blown into the pc.  Some of it will also get blown out of the pc, but the bottom line is that if you don't have a filter, some of that dust is going to settle on the interior of your pc.  Positive pressure does not guarantee that all of the dust that comes into your pc will also get blown out.

He's using the GPU rad with the air flow going OUT of the case. All that filter was doing was IMPEDING airflow through the rad, it was not acting as a filter. Paying attention to direction of airflow is importing when making an argument.
 
'Positive pressure does not guarantee that all of the dust that comes into your pc will also get blown out.'
 
That's not the idea behind positive pressure. Positive pressure is so that dust is not sucked into the case. It is not to blow dust OUT of the case. This is why you use filters on the INTAKE so dust does not enter the case. This is why you have more CFM as intake air than you do exhaust. So that clean filtered cooling air is intake and warm air is exhausted.

spiffy_1
If it was me, id put the triple in the roof since its exhausting air anyways and your CPU doesn't need a triple radiator.  Id put your 3090 on the front of your case so its getting fresh air without the heat wash from the CPU.  Then I would put a fresh air fan intake on the very top of the front of your case to provide cooler air for your CPU cooler.  I've never understood the dust filter on the top of a case since you're blowing air out of it.  

spiffy_1
If it was me, id put the triple in the roof since its exhausting air anyways and your CPU doesn't need a triple radiator.  Id put your 3090 on the front of your case so its getting fresh air without the heat wash from the CPU.  Then I would put a fresh air fan intake on the very top of the front of your case to provide cooler air for your CPU cooler.  I've never understood the dust filter on the top of a case since you're blowing air out of it.