Re: Eagletac D25 Clicky Series Round-up Review (D25C, D25A2, D25LC2 - XM-L & XP-G)
I can add a little information about the D25A clicky (i.e. the single-AA version with click-switch control in the end-cap). It seems to have some important design differences from the two-AA version (e.g. a non-reversible barrel, no memory of last-used setting).
As a light-weight hiker, I am always looking to save a gram. So I really like:
(1) Low weight (22 grams after removal of the clip);
(2) Knurled barrel (which grips firmly in my home-made head strap);
(3) Floody beam from the XM-L2 U2 LED (good for headtorch use, not for long spotlight throw);
(4) High efficiency (specified with unstated battery type as 150+ hours in moon mode - which at 1 lumen is just useful, or I guess nearly 50 hours in non-moon low mode - which at 4 lumens is a good compromise for many tasks). Also current regulation and compatibility with diverse AA-size battery types;
(5) One-hand operation via a rear mechanical switch (easy to find, even on my head, and no parasitic drain when clicked off);
(6) It tail-stands just fine (fit a latex-glove little finger to the front for candle-mode);
(7) The interface starts in low mode then ramps up and cycles through various strobe - flash - SOS modes on subsequent half-clicks (with a front-twist for turbo / strobe cycle). For others wondering, 'beacon' is a very slow flash.
For me, torches with side or twisty switches defy quick operation on my head. Those which start bright have destroyed my night vision before I can work out their minimum useful setting - so they get used brighter with a big hit on battery life (meaning a weight penalty for more carried batteries). If I ever need to frighten the bejeezus out of something with a 1AA torch flash (??), I reckon I can remember to screw it into turbo mode first! For me, a torch does not need a memory (provided it starts at low intensity), and I don't want parasitic battery drain between hikes.
It was easy to remove the clip to save a few grams, using a hex-tip screwdriver. A 1.5 mm tip was fine if used carefully (most people are not going to order, then wait for, a custom 1.55 mm tip).
Possible concerns for other users are:
(1) No battery lock-out function. You can not simply unscrew the tail or front cap slightly to ensure that the torch can not accidentally be clicked on, thereby flattening the battery while packed. You can not improvise lock-out with teflon tape or the like - the circuit path is not arranged that way. But the tail switch is recessed enough that some care when packing will minimise the risk. Or in desperation you could reverse the battery or fit something like a small chair-leg tip over the switch - I have not bothered.
(2) The tail cap has a flimsy thread and o-ring, below which are a fall-out washer and switch mechanism before you can access the battery. I found this almost impossible to replace without damage once a battery was installed, even without the pocket clip. The solution is never to remove the tail cap. Instead, remove the front section (which has a better design of electronics, thread and o-ring to avoid damage with careful use). This is in defiance of the manual text on battery replacement - but it matches one of the illustrations. Otherwise the torch is very robust for the weight. By the way, that rear (steel) washer is important to centre the switch and avoid closing the circuit without passing through the switch. So if you want to save a few milligrams by swapping it for something lighter you need carefully to match the dimensions.
(3) No Morse-signal mode (but torches that include this usually bury it so deep in the interface I could never find it in a hurry, and I have forgotten most of the Morse code - so I am satisfied with the pre-programed SOS).
(4) Very 'cool white' colour rendition overall, with some yellow rings when used close-up at higher settings, but you can choose a slightly less efficient LED for a 'warmer' colour or a different beam profile, as mentioned on the Eagletac website.