I opted for the felt-covered version in the hope that they would be slightly better at rejecting dust etc in the field. Also, they were a few cents cheaper. I recall seeing SONY and other pro lavalier mics with the perforated front, so maybe this design favours voice pickup?
I doubt that my old ears would pick out any difference, but it would be interesting to hear back from any one who has detected a difference between the two versions, or can explain it.
