Prime looks pretty nice but it's derive from the HP38/39 series rather than the RPL machines which puts me off.
I've got an HP35s here which is the daily driver and I used an HP50g for many years. The 50g was super nice. It was a fully blown computer and development platform rather than a calculator. But keeping the entire machine model in your head was difficult unlike the 35s.
I've had a few calculators over the years: Casio FX-83, 85, 7000, 4000F, 991MS, 991EX, 991EXPLUS, 991EX, 7000G, 9850G, TI 80,81,82,83,85,86,92,nSpire,nSpire CAS, HP 48SX,GX,50,33s,35s plus some I'm sure I've forgotten
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. 35s is about right.
Edit: Honestly most of the time I use LibreOffice calc, SymPy and formerly mathematica (basically until I couldn't find someone else to pay for it
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