What's wrong with Mach 3?

The two superpowers slaved away in their secret lairs, devising more and more cunning and elaborate weapons of mass destruction to knock out the other guy. I baled on three blades, thinking that was quite enough, and actually thinking that Mach 3 gave me a pretty good shave. Expensive, yes (though I had to protest when Helen exclaimed at the supermarket checkout at how much they cost, when they're about the only cosmetic item I ever buy). But a good shave is a good clean professional way to start the day, and using a disposable is on a par with using a shard of broken pottery.

It has a little strip that supposedly moistens your face as you go, but in fact the purpose of which is to gradually wear away and show you when your razor is getting close to needing replacing. It's a more efficient way of finding out than slicing your face (it's the blunt blade, or rather set of three, that cuts; not the sharp one). Fair do's, sir, as Howard Moon would say. There's always a delicate balance between getting just another shave from an old blade; and cutting chunks out of your face and having it bleed for hours in meetings, inviting pity and scorn.

But recently the blade's stopped sitting properly in the razor, and falls out twice or three times as I shave. Perhaps I just need a new razor. Perhaps they've changed the design a little. Either way I'm tempted to go nuclear and try a four bladed razor (I'm assuming there is such a thing: why would they stop at three?).