Remember some years back when Gillette and Schick seemed to be locked in death match as to who could put the most blades on a razor? It was if they believed that the more was better until someone realized that A.This was foolish and B. There was an outside limit as to how many blades you could put on a razor and not go into diminishing returns. Or, when you got to the Schick or Gillete Twelve to the Fiftieth power, no man could even lift it much less afford it. Of course, at that point it was attached to your wall and you just rubbed the part to be shave against it. (This would have had some obvious drawbacks but it never got to that point.) At the cost of blades, they should all function better than, in reality, they do. I find the differences between three and six-apparently the surviving number in the Blade War- to be minimal. For face shaving I'm partial to a Merkur DE and would use it on my head but, for whatever reasons, that always ends bloodily. I think the Merkur blades are better, more affordable and last longer so for those who have mastered double edging your scalp, that's my answer. Or we could look forward to the Whoever Octo which is the Quatro doubled.....