My primary use case is augmenting my napkin math. That doesn't necessarily mean doing all calculations on the calculator, just offloading the parts where my int

My primary use case is augmenting my napkin math. That doesn't necessarily mean doing all calculations on the calculator, just offloading the parts where my intuition is likely to fail, to help narrow down the result. For anything where precision and correctness matters (long formulae, sums of values) I'm usually using more specialized tools, from math software to spreadsheets. They could be tested and verified, unlike calculators. And that's exactly what I don't want to see in a calculator I use, because it turns it into something more heavyweight. Calculator is a bicycle for me, not an earth moving machine.