Indeed, we all HP fans must be extremely grateful to Jean-François Garnier for creating such wonderful emulator firstly, then making it publicly available on-line for free, and last but nor least, including with it a most generous provision of ROM images, the Math ROM, JPCROM, and Forth/Assembler ROM among them.
That makes every HP fan a potential HP-71B user, both for fun and for profit. In my own case, I fire it up under Windows XP each and every time I need to make a quick calculation while working: I've found that making the most complex computations with it is unbelievably fast, both while entering the expressions and when executing them. This includes heavy statistical calculations as well as very complicated actuarial formulae, to name a few.
Also, with the incredible capabilities of the included Math ROM, I can solve equations, compute integrals, use complex numbers, or do matrix computations at once, from the command line, in mere seconds. Actually, I can do most anything in the time that others would need just to load their programs or turn on their physical calculators. So, Emu71 has become second nature for me.
As for the Math ROM, it was and still is one of the most powerful pieces of software for handheld computing ever made. Under Emu71 it's become blindingly fast, and with the help of the simulated 80-colum HP-IL display, working with large matrices and long programs is extremely easy.
There's also the fact that the Math ROM's feature set can be put to uses non-mathematical in nature. For instance, I've used matrix operations in such programs as my "Modest Mater" (which solves arbitrary N-move chess mate problems) or "Sudoku Solver" (which of course, solves Sudoku puzzles), both having very little to do with math. Matter of fact, anytime when you need to make a fast temporal copy of a large bunch of data, such statements as MAT A=ZER, MAT A=CON, MAT A=(expression), and MAT A=B are incredible
time-savers, even if you never need to do any arithmetic with the
data thus saved and retrieved.
Most other functions can be put to nonexpected (or expected) uses, such as complex numbers as coordinate pairs, Fast Fourier transforms to help speed convolutions (for multiprecision computation, for instance, see my "Fantastic FOUR" article/program), etc.
In short, both Emu71 and the Math ROM are unbelievably good software, and both can be used extremely profitably even nowadays, if nothing else as an über-calculator under Windows which runs rings around any other hardware/software device in terms of speed, simplicity, and convenience.
Formerly I did use either HP-41CX or HP42S emulators but after I got the emulated Math ROM I've never used them for on-the-fly calculations anymore, because when I'm at work, inmersed in some complicated actuarial project (as if there were such a thing as a non-complicated actuarial project!), even in the client's presence, I've no time at all for RPN or RPL vagaries and cumbersome interfaces, I just need to key in expressions as fast and easily as possible, hit ENDLINE, and voilá, perfect results instantly, editable, saveable, copy/paste-able.
And don't you think that "expressions" means a puny combination of numbers and arithmetic operators, I mean using the full Math ROM feature set, named variables, loops, and even defining and calling multi-line user defined functions or subprograms on the fly. Try and do that, or the equivalent, any other way, at full speed. Particularly, try and do that using any RPN/RPL emulator or physical machine. You'll be hardly starting by the time I'm done with the calculation.
So, most sincerley, thanks again to Jean-François for it, he deserves all our support and appreciation for his disinterested efforts in benefit of the HP community.
Best regards from V.