Hi, I have a question about blades. More precisly, when you buy blades in large quantities, like 800, or so, what happens to them after some years? Lets say I want to buy 800 blades, because its just cheaper that way. I would use about 50 a year, so I get about 16yrs worth of usage. But, will they not start to loose their edge eventually? Like when people find of Gillettes and things with old blades, those blades are useless.