To be more positive, the D80 is a pleasing looking handy thing with unique characteristics, and could be brought up to date with a decent FET+n driver, e.g. a BLF/Lexar/Texas Ace, running whatever modern firmware that can still operate with a tail clickie, rather than an e-switch. 7135, or dual bank 7135 for efficiency and steady output at modest levels.
Preferably a straightforward simple intuitive UI that doesn’t require a crib sheet to comprehend. Perhaps a couple of programming options, but no more.
The original driver was very poor, it even had an incorrect value resistor that prevented the very weak FET from turning on fully, restricting tailcap current to 1A or less. DEL discovered this, and showed us how to improve it. However it still suffered from objectionable PWM, inefficiency at the lower levels and poorly spaced modes. It must be binned.
That short reflector and head is rather unique, and the concept should be retained.
Keep the tail clickie, don’t be seduced by side e-switches.
Together with a DTP copper MCPCB and a modern smaller LED (original was XML-2) with higher surface brightness for better throw. As supplied, with non-DTP Al MCPCB it was thermally challenged as soon as you tried to pep it up. Though the basics were there, integral shelf and twin screws to clamp down the MCPCB solidly.
However IIRC some who tried smaller LEDs at the time found that it was difficult to get the reflector/LED focussed satisfactorily and without artefacts in the beam, it is very sensitive to e.g. the thickness of the locating piece, and the large reflector hole, sized for the XML-2 doesn’t seem to work so well with smaller LEDs.
Perhaps the reflector could be re-tooled, just by reducing the size of the hole to suit smaller LEDs. Or it might require re profiling of the flatter part.
The beauty of the D80, to my mind, is the neat compact design, and it feels good in the hand. The workmanship and surface finish was great.
It makes a C8 feel crude and unwieldy.
However for an enthusiast it was no good, basically just a host to spend the same again on as a modding project. Not a well rounded BLF design that could be used as-is.
So, my list of essential changes would include:
1) New driver, in a standard size (e.g. 17mm)
2) DT|P copper MCPCB
3) Updated LED with reflector modified and tuned to it.
4) Body tube length optimised to take flat top, button top and even protected 18650 cells. Sadly this may require changing the stud contact on the driver (which I like very much, much better conductivity than any springs) for a spring.
5) Spring(s) to be good BeCu, e.g. Blue type. The days of faffing about with spring bypasses should be over, at least for BLF designs.
6) Short 18350 tube also to be available, with liner to also take 16340, CR123 etc. Some have cut down the 18650 one to make a very neat and handy package, it would be great to have this option.
7) Forget the latest fad for 21-70 cells, that would bulk it up and lose the neat compact nature of this, and further complicate use with 18650, spring lengths etc. And I’m pretty sure they will continue to be a fad, as well as the dimensions not being well standardised, making tolerancing of the tube and selection of compatible cells a guessing game. Having a 1” OD tube is important for some applications, it is the standard for many mounts. Yes, it might be possible to fit a 21-70 into a 1” tube, but I think you would lose the chunky grippy nubs and stout wall thickness that make the D80 so tactile.
8) Change the thread of the switch retaining ring to LH, so it doesn’t keep coming loose when you change cells. Convoy knew this years ago.
9) Optional FET remote tailswitch assembly for hunters, curly lead and pressure switch, with UI option to lock into turbo-only output. Maybe in a package with some flip on colour filters.
Give me 1-8, at a BLF price and I would buy a couple. But overall that would be a lot of re-tooling to get to the product that it should have been originally.