I’d come across sinks with boiling water on tap during my time working in Australia. When our existing filtered water faucet broke I did a little investigation on under-sink water heaters and the Insinkerator units had the best reviews.
Installation was very easy. I use it for my morning tea, and my wife likes using it as a “pot filler” to fill pans for pasta. The super-hot water is also good for cleaning, but take care you don’t burn yourself.