I bought an HP 12c to have the very limited experience of programming in a nice form-factor device with the classic keys. It is also faster to use thus calculator in the desk than opening it in the desktop.
I gave away my HP 12C when I bought a 19B back in 1990 and regretted it some years later. Recently I've been using a 12C on my phone and am now seriously craving a real HP 12C again. There's something about that calculator.
There's a Swiss company making impeccably high-quality versions of the HP Voyager calculators, based on a modern ARM processor. Well worth checking out if you're in the market for a 12C.