I dont know some of the brakes I shoot next to these days lift small children and toss them a few feet with concussion.
Stones, grass, etc flies and lands somewhere.
Again than it comes down to a decision....
Smaller opening only finer seive material can enter.
Larger opening may allow for more material but easier "shake out" of debris and the ability to accept different barrel sizes is a plus.
There is no one correct answer, user preference and assumption of conditions I guess
If debris is a concern you could always field strip some 550 cord and use the exterior inside the barrel channel as floss.