I think YMMV so much on this because of the 'mileage' difference on faces.
I'm of Asian and Hawaiian descent in my mid twenties, so I have virtually no growth on my cheeks or neck. I'd say i have maybe 6 square inches of growth to shave.
On the other hand, some people have over 5 times that amount of area to shave.
The amount of hairs shaved per square inch also varies.
Also the thickness of each individual hair.
Then there's also the number of passes per shave.
Too many variables, so the only way is to try it for yourself.
I'm of Asian and Hawaiian descent in my mid twenties, so I have virtually no growth on my cheeks or neck. I'd say i have maybe 6 square inches of growth to shave.
On the other hand, some people have over 5 times that amount of area to shave.
The amount of hairs shaved per square inch also varies.
Also the thickness of each individual hair.
Then there's also the number of passes per shave.
Too many variables, so the only way is to try it for yourself.