First thanks much to everyone on this vibrant forum. You've really assisted in my calculator decision. I've joined to provide some feedback to HP which seems to be following along with our experience with the prime. I love hp calculators of old, have been infected with the rpn meme, so I'm in hp's thrall and need to help them to build the tool I want.
1) Loved my hp15 back in the day. It broke due to water damage.
2) Replaced with an HP48S, love it, was stolen after 2 years.
3) Replaced with an HP48G, even better but now after... 20 years! of use the keys have intermittently stopped working on the lower right. I could disassemble and fix but it feels like its time for a new machine since this thing was always a little pokey.
I looked seriously into the Prime, downloaded the emulator (v5106) and switched to rpn. Immediately the emulator was freezing and crashing, I couldn't get anything done, using it was treading a minefield. I found your forum to confirm that the Prime really isn't fully baked in rpn mode. I love that the enter key is in the right place but am not willing to live with and depend on beta software. Maybe in a year or two the bugs will be worked out and I can take another look.
General discussion about desk calc:
1) The world has moved on from the limited symbolic manipulation that's in these calculators. For algebra really I think the bar has moved too far for hp to code their own solution. Wolfram alpha is the benchmark, its what my children use to check their algebra and calculus homework and its just so terrific to have a complete symbolic/visualization solution for difficult issues I may be working on. Maxima is a reasonable free solution. I would love to have access to that sort of power in a battery powered desk unit.
2) The ipod/iphone can run hp48 emulators, but that means needing to have a device charged and doesn't have the tangible feel of nice buttons. Screen is too small, ipod mini is too big and serious for a desk calc and also has the battery charger issues.
3) I'm also versed in emacs calc package, I like its rpn too but still very inefficient for a desk calc so poor battery life.
4) I think its fine for hp to innovate their calculators but its weird that hp has moved away from such a deep and well thought out history. Not to say new things are always bad but there seems to be a loss of respect for the excellent design that came before.
5) Buttons and key placement are very important. You could produce a professional edition with the keys from a 41cv? I want to own it and use it for another 20 years so build it well, I will pay. Make something that the world lusts after, thats a joy to hold and use! Maybe create a cheaper edition for students and use the crappy keys there?
So, long story short I've gone with that old obsolete hp50. On sale on amazon for $80. Yeah, enter key is in the wrong place but I'll live I think.
I'm very excited to try out the hpgcc3 c toolchain. That could be amazing!
Summary for HP:
0) The prime was built by a dedicated core. Thank you so much for trying and building it. Its amazing and huge system.
1) Please fix the prime's rpn mode. It appears to be unusable today. I was confused by how bad it was but maybe I was unlucky with my testing. It appears that rpn mode didn't get much test coverage.
a) For v2: I think you've wasted a bunch of space at the top of the prime keyboard. Touch screen is a win so selector isn't needed. Either implement soft keys on a larger screen or a grid of programmable keys.
b) Sorry you moved away from regular batteries. I'm not interested in charging my calculator I want the batteries to last weeks without thinking, swap new ones in quickly and move on. It aint a phone!
2) Key feel is important. Dig deep and build some nice keys. Ceramic keys with a nice glaze? Seriously what happened here? I'm not harkening for the past like rpl, just something thats nice to use. Make the customer want it!
3) RPN algebra is important. Provide better ways to manipulate: control factor and simplify and solve. I am tempted to implement my own system just to give an example. Emacs calc is almost there in some regards.
4) Spreadsheet is a fantastic feature. I totally want it. RPN spreadsheet inputs to form an algebraic string. I can imagine a day when the rpn stack acts on a column in a spreadsheet? Imagine the unit math! Imagine the base conversions! Possibilities are amazing!
Thanks again. I really look forward to what you will build next.