I like the construction of these calculators, but I&#x27;m not a huge fan of the programming language.  I think the Casio FX-4000P &#x2F; RS EC-4020 was the pinnacle, but this was a few years later (and admittedly, not as numerically good as the HP).  Editing was far easier with the dot-matrix display.  Compare the programs:<p><a href="http:&#x2F;&#x2F;www.rskey.org&#x2F;CMS&#x2F;8-programmable-calculators&#x2F;299-fx4000p" rel="nofollow">http:&#x2F;&#x2F;www.rskey.org&#x2F;CMS&#x2F;8-programmable-calculators&#x2F;299-fx40...</a><p><a href="http:&#x2F;&#x2F;www.rskey.org&#x2F;hp15c" rel="nofollow">http:&#x2F;&#x2F;www.rskey.org&#x2F;hp15c</a><p>Casio improved the fx4000p, but I think the design was not as coherent: <a href="http:&#x2F;&#x2F;www.rskey.org&#x2F;fx4500p" rel="nofollow">http:&#x2F;&#x2F;www.rskey.org&#x2F;fx4500p</a>