Well, the assessment that 7 to 8 shaves can be had with a Personna Med Prep blade before needing to chuck it, is pretty dead on. Tossed my first one today after the 7th shave.[/QUOT
I'm getting ready for shave 12 today with my blade... it still cuts effortlessly...
I may toss it after this shave, not out of necessity but just to move on to a different brand of blade in my stash.
If you can hit 7 shaves with one, see if you can go to 10. These blades have longevity even for a newer user.
Just my 2 cents!
John H.