Neu Motors and dust

[Shark413]

I got a question for any Neu owners out there. How many of you are using some kind of dust cover on your motor? Is it really necessary? I assume the holes are for cooling, and the motor has roots in the aircraft world where dust isn't as much of an issue. Does covering the holes cut down on cooling but keep abrasive dirt out of the motor? Is it better to leave the holes open for cooling and just blow the dust out on a regular basis? If left uncovered dirt will probably cause more bearing wear, but would this be partially offset by the additional cooling? Anyone try foam filters to cover the holes? Most brushed motors have open endbells and some even have holes/slots cut in the can for cooling.