Which fans are the best for my AIO?

"Best” isn’t always the best, in this case, since someone may opt to go for a RGB build with fans that may perform well on a radiator, but not the best. That aside, static pressure is what you'll want to go for when looking at options for getting the best fans for your AIO.

Instead of going with a push/pull configuration as it was usual before, now a 30mm fan on one side of the radiator would be what you seek for higher static pressure performance. Not only do you save space if going 2x 25mm vs 1x 30mm, but more often than not it will also help in tighter spaces and cases.

Keep in mind that these higher static pressure fans may be a bit louder than your regular case fan, but that's the beauty of being able to control RPM and lowering the noise while still maintaining high performance on your AIO, and even watercooling. Some go the easier route and get a bundle that was made specifically to perform at higher levels while also including the best set up for your CPU, such as the iCue Link Titan 360 RGB w/RX120 Max (4) bundle.