Sigh. I'm tempted, especially by the 16 model (have been kicking myself for a very long time for not getting one or three when they were in production), but the membrane keys are a killer. Next to RPN, the greatest feature of HP calculators were their solid, no doubt keys. I did a math heavy semester of general chemistry with my 28S (which I still have, along with a backup I got on eBay) without making a single error, which rather surprised me.
