In smooth air, the DCs are more comfortable to me, but I dont like the sense that they might shift on my head if I move too quickly. Despite having the proper part number as confirmed by BMW and others online these do not fit the low profile rails on my E91. Used it for almost a monthPros:Noise cancellation while on music is good. To be clear, this device is a bluetooth RECEIVER, digital to analog converter and amplifier. Gives me the cushioning I need dealing with plantar fasciitis. I loved it so much for traveling, The beads are not uniform and theyre definitely not size 11. Design: Mediocre, and it doesnt hold in ear very well. Support answers the phone quickly. Got them and wore them all day.