I am on a one a week bent right now. But a couple of weeks ago, I started using a vintage blade that I so enjoyed that I am just beginning to creep past week two. So far so good (other than the rust that's showing up from leaving it in the Den), but I can definitely feel the difference today vs two weeks ago. I am going to venture a guess that I would want to home after three weeks or so of dedicated shaving.

I am sure I could go longer... but why lol? I love running my blades over my rocks.