Another point in favor of leaf shutters (I believe) is that the motion of all the shutter components is totally concentric, thus (at least theoretically) any vibration caused by shutter leaf motion is self-cancelling, making the minimum potential vibration level zero. If you do get a bad vibration level with a leaf shutter, in my experience it's down to a stiff cable release or release lever.

Merry Christmas to all,

David