Astra SP (15.5) - Counted 1/2 a shave for two passes on the back of my neck between barber visits. Blade performed fantastically, up until it took 4 passes and touch-ups to complete yesterday's shave. Looked at the Rockwell this morning and thought, I don't need four+ passes and chucked the blade into the disposal bottle. Spending $0.10 (or less) for 15 full shaves was surprising.