I'm looking into buying a high-end electrical shaver which I can use not only for my beard, but also my head. However, electrical shavers are designed to collect the cut hair below the rotating or oscillating blades, which works fine when cutting hair on the face. Using the shaver on the top and the back of the head causes it to be held upside down which makes it questionable whether it still works fine and without a multiplication of blade wearout which might be caused by the same hair being cut multiple times instead of falling below the blade.
Can I ask this question on engineering.SO? Is there a better place?
Like I mentioned in the title, I'm not looking for a product recommendation, but a design type (rotary or foil-type design or else) which fits the needs best and an argument that the use doesn't cause unnecessary wearout.