While the unit that I use every day is the HP15c (more now with more programs due to the extended memory we discussed in the previous blog), I realize that the best HP non-graphical calculator is the HP42s. (other competitors are the HP67 and the HP41c calculators). I have my own that I wll not part from. It joins the HP42 compatibility with much more memory, better speed and a very good extended set of functions covering matrix, complex and others. It only lacks the expandability of the HP41 - the rest is better in my opinion - even the keyboard feel is a the same level.
We have now one for sale, at 325€. It has very minor dents in the screen bezel, but it looks wonderful and it has excellent screen. Grab it while it lasts!!