more so the odd conversion and the wind side.
I use it every day for fuel litre/kilo conversions, well not "every" day, but you get the drift. Everyone else I see uses electronic (usually phones) calculators - and I have seen the typical "100 times error" turn up which doesn't usually happen with the whizz wheel (as you have to do a rough sum in your head for that bit every time anyway).
Flying in Europe, I occasionally play with it in cruise on the days I am not reading the paper, to remind me of the days (in Australia) when I was
really 250 miles away from a decent airport. At those times, I check the IAS and Mach against the TAS on the FMS - but just from curiosity about the accuracy of the CR-2...