My old rechargeable Philishave finally died, so I had to promote my backup one to prime position. Previously, I'd only used the backup one on long trips. I've gotten used to the older double action shaving cutters, so I stuck to the same design for interchangeability, rather than update to the new triple action or underwater ones.
But the price of replacement double action cutters is about as expensive as the newer ones, and I noted that they'd gone up a bit since the last time I bought a set. So I thought I should stock up on them when I saw them going cheap. As a result of which I bought another 4 mains powered Philishave units. Beats me why it's cheaper to buy the whole shaver, than to buy the three cutters inside them.
The same thing happened when I wanted a spare battery for my Siemens mobile phone, it was much cheaper to buy the phone than to buy the battery inside of it.