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Well I guess I'd been living under a rock. I only just found out about these in the past week or two.
HP 15C Collector's EditionThe HP 15C Collector's Edition seems to be generally available, I had one delivered next day to me last week from Amazon. This is since Moravia became an HP partner for calculators, and a bloody beautiful job they've made of it too. As I understand it, HP also offloaded their calculator marketing interests between Moravia (EMEA) and Royal (North & South America), with both becoming marketing licensees using the HP brand.
ISTBC, but as I understand it the technical work, manufacturing and EMEA marketing is arranged by Moravia, with Royal acting as the marketing for the Americas.
The keyboard's completely reliable, and is more positive and clicky than my three original 15Cs, all of which are a bit spongy to some degree or other these days.
The HP 15C remains on my benches, it's just so immediate, plus of course it has a great persisted ENG format mode (although I do admit to keeping various incarnations of Casio's FX100D like the 115D/570D/991D around too for exactly the same reasons).
C47 CalculatorThe C47 is a progression of the WP-43S/WP43 and C43 fork, built on the shoulders of the WP-34S. The WP-34S is already a great solution for EEs, with things like direct parallel R and L calculation.
The WP-43S and the WP43 are the same thing, a minor rebranding.
Like the HP 15C, these are engineers' calculators for doing numeric calculations: if you're looking for something to do your analytical algebra or calculus homework, these probably aren't the calculators for you.
Frankly, although I was well aware of the WP43, I considered it to be vapourware unless you were within the clique of developers, it had gone on so long I had given up. So imagine my surprise when the derivative, the C47, came out alive and well.
As I understand it, the WP43 and C43 were designed with a SwissMicros hardware platform in mind (eg DM42 with a new keyboard layout), and for a while SwissMicros were intending to commercially distribute a WP43 calculator. The commercial arrangement fell apart (
seemingly disagreements in the direction of travel between WP-43S software developer(s) and SwissMicros), leaving a bunch of code and documentation with no hardware to go.
At this point most of the WP43 team joined the C43 team, and the C47 was born, explicitly designed to work directly on a SwissMicros DM42 without needing new keys, but would need a bezel/overlay for secondary functions (see later regarding the bezel).
The biggest pro of the C47 is its configurability, including menus, tailored to the end user's requirements. I particularly like the customisable thousands separators both before and after the decimal point, for example. In my limited us over the past few days, it's a worthy contender as a WP-34S successor, and I prefer it to the DM42 stock firmware.
Regarding the bezel/overlay for the secondary functions, you're going to need one. You can either get a stick-on bezel, or a removable tabbed bezel that slips in neatly into six small receptacles around the DM42 keyboard. I don't know why you'd go for an adhesive bezel when the removable tabbed version is such a good solution. The tabbed C47 bezel I ordered comes in two options: standard and "Big Alpha", I chose the Big Alpha as my eyesight isn't what it was when I was 15. It's very readable, both in font size terms and because of the colour contrast.
To work on the DM42 without new key caps, and only one function button, something had to give. So the fix was to keep one function button, but press it multiple times. I was sceptical, but in practice it works extremely well.
The biggest problem with the C47 right now is the documentation: it's dozens and dozens of separate PDF files. With the help of a handful of Youtube videos, I managed to get started. Be aware that the calculator is still heavily based on the WP-43S, which does have fairly decent documentation, albeit the keystrokes now are likely wrong!
I also find the C47 UI to be a bit laggy. Not sure why that is, as the DM42's is great in this respect. Edit: it's much faster with the USB cable plugged in.
Irrespective, the C47 is highly likely to become my favourite calculator, if it isn't already...
Link to the bezels I bought, they arrived by post in precisely a week:
https://www.hpmuseum.org/forum/thread-20113.html