For anyone who wants to try a Model M or had them and misses them, Unicomp continues to make them (in the original factory): https://www.pckeyboard.com/. They're even made with USB now, so PS/2 adapters aren't necessary :). Of course, there are also a bunch of older ones on eBay as well - as bstar said, they're built like tanks.

I used a Model M when I was younger and loved it, I'd probably get a used one or buy a Unicomp one if they weren't so dang big.