Shaved head for 20+ years here. I use Gillette and get at least 8 weeks shaving daily without issue (ie. 8x7 = 56 shaves or 350% of your reported longevity). Th

Shaved head for 20+ years here. I use Gillette and get at least 8 weeks shaving daily without issue (ie. 8x7 = 56 shaves or 350% of your reported longevity). The trick is wet shaving (in the shower) with good lather (I use soap). Dry shaving is an anachronism in this day and age, save for water-scarce or highly unsanitary environments, where I prefer to just not bother. As an aside, I'm pretty sure they are incrementally tweaking the chemistry of the blade-front indicator to break down more rapidly, which destroys the uniformity of the leading edge. IMHO older cartridges actually last longer. If you find a stash in the developing world or some other slow-moving place, buy them.