In reply to Cheese Monkey:
Guess it depends on the size of the micro, I think it would take less than a fall to deform the smaller ones enough to reduce the strength to below the rating. In a good placement they're probably more likely to fail with a wire snapping so any damage to the wire would be more worrying to me than damage to the head. Some of my brass offsets are gouged a bit but the wires are fine so I'll still use them.