hi everyone, i just signed up to say that the honeycomb grills on the 180mm fans are there to consistently direct airflow upwards rather than the air move about the case, protection is secondary (holes are too big for screws not to fit in). there's a link about a study on using different fan grill designs and as far directing airflow, the honeycomb grill works best. 'can't find the link though. :(
ninja edit:
found it!
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