How do you know when it is time for a new razor blade? How often do you change b!

How do you know when it is time for a new razor blade? How often do you change blades?

(Hard to find a good category for this question. I tried in Beauty & Style, but that seems to be mainly about women's style, not men's.)

I wore a beard and mustache for the last 20 years, now I'm shaving again. Back then, the big thing was a razor with two blades - now they're up to 4. I way out of touch.

So how do you know when it is time to toss the blade in your razor (or your disposable razor) and use a new one? How long do you go between?

Do the extra blades on the razor make a difference for you? I can buy a dozen one-blade disposables for the cost of 4-blade titanium cartridge, and it is hard to see how the expensive cartridge is worth the difference. What's your experience?

I use an old fashioned double edged razor. I was surprised to find that it worked just as well as the ones that have multiple blades. I buy a 10 pack of double edged blades at WalMart for $1.75, each blade lasts about 2 weeks. That's a lot cheaper than the cartridges. But then again, that's just what works on my face, your mileage may vary.