With the rise of so many headlamps on the market now, I thought it prudent to discuss qualities of what you find makes the best headlamps — and what might detract from them.
IMHO
Pros:
1. Dual optics
2. Simple UI
3. Centered emitters
4. Easy to rotate (up/down)
Cons:
1. L shape
2. No temperature cut off
3. Heavy
Doesn’t yet exist, but “best” would be:
- Two buttons: one for on/off, and the other for mode selection
- A fully customizable mode selection UI
- Red emitter
- Lock out mode
- A low power on shortcut
Available Modes would be 1 lumen, with adjustable output from 1% to 100% (10% stepping is fine). Then a UI that would allow for the order and customization of the chosen modes. So, I could choose 1 lumen at power on, next would be 50, then 100, then Red at 50. That is personal setup, someone else would choose 50 on then 100% only. Its their choice.
So, a current good headlamp is the Skilhunt H03C RC. Has multiple colors, right angle so you can use it off band, lightweight and small, lockout mode, great head strap. Detractions are that you can’t adjust the red emitter power output, and can’t customize the UI.
A problem with all headlamps is there is no way to get to low power. Its 2am, you’re camping, and you reach for the headlamp. When you turn it on you totally blind yourself.
I agree, best headlamp doesn’t yet exist, but “best” would be:
Host and optics - H04;
Driver- synchronous boost >10W driver ( Zebralight) ;
Best UI - something similar to Olights, Thrunite ( I coded my own);
Best LED - Warmish (4000-3500K) Hi-cri led;
rechargeable Li ion battery; 18650 ideally
onboard charging
smooth ramping UI
rotatable range (up/down) close to 180 degrees
1000 max lumens
The D25’s are my favorite headlamp design.
Weight, balance, comfort, adjustability, beam characteristics, UI.
Kind of depends on the task at hand. High CRI and good optics always.
By far my most used and useful light is a headlamp.It is absolutely perfect as an EDC and urban dog walking light. Perfect for working in equipment cabinets with its magnetic tail. Most useful moonlight modes of any light I own. Beaded optics give excellent beam profile and it is perfect for nearly all up close work. The clip is excellent and allows for it to function as a “headlamp” via shirt, jacket, backpack, and of course on a hat brim. It is an EO2 II. There are jobs, or activities, that require more output or runtime than a AAA can provide. For me, I would like everything that the EO2 II has only with an 18560 and that would cover everything. However, some people need more throw and some may need a red light. A great light is largely determined by what you need it for.
I like smooth ramping, so my favorite headlight is the Lumintop HL3A.
I also like L shaped headlights, warm tints, and throwy emitters like the SFT40.
I know that the SFT40 doesn't come in warm white, so there's no way I can have it all.
Good position of the Switch, UI that works with simple clicks.
Wizard Pro gets everything right. Not sure how other headlamps can possibly be sold 
Cyansky HS6R (but lighter). Or D10 with 5000k Sst40. I have both. Aside from the blahs UI it’s perfect and cheap.
I really like the Armytek and Zebralight UIs. Otherwise, warm to neutral high CRI output and a floodish beam. Battery type of size is application dependent but decently tough and waterproof.
First, a wide smooth beam pattern. It needs to be able to go from moonlight to 1000 lumens. It should have memory but it should also be able to come on in moonlight or turbo. It needs to be way under 5000k. On board charging. Waterproof, tough, reliable. It needs to go in and out of the headband easily. I realized a few months ago that none of the head straps I have are really comfortable for more than 15 minutes. I started trying to figure out a way to make a nice cushioned pad of some sort. I considered leather or other thick but soft material. About 10 years ago I bought a three pack of that Sham Wow orange material that used to be advertised on television a lot. It works perfect. On mounts where the top strap is removable I take a piece that’s big enough to fold in half and just a little bit bigger all around than the head mount and make a small cut/slot near the top fold. So it’s just held in place by the top strap. On mounts where the top strap is not removable I just cut a strip about as wide as the band but long enough to double up and just tuck both ends in through the holes about a 1/2 inch with the main strap. They are all very comfortable now. So a comfortable head strap even if you have to modify it yourself.
USB recharging function.
Way yo use AA batteries in an emergency.
That is my opinion.
My Zebralight H600w ticks most boxes for me- low low from off, access from high from off, enough modes to dial in to correct level without wasting battery or making do with insufficient light. Lightweight, compact form factor. Comfortable head strap.
Only gripe is when it’s raining, drops of water pool on the lower part of the bezel which refracts light into my glasses.
T-shaped body vs L-shaped. Hate asymmetry.
Onboard charging would be nice/convenient.
TIR lens a must.
Simple UI of on/off with a click, press’n’hold from off for moonlight, 2click for highest, press’n’hold from on for cycling modes.
Warmer CT vs Angry Blue™
NO BLINKIES.
I am of the opinion cheaper is better with headlamps. They tend to get banged up and full of caked on sweat.
Caked-on sweat”? I can’t even express how much “eww” I’m feeling right now.
Wuben H1 is it for me.
Cool white but with great clarity plus it has a separate lower output warm white up close flood and a Red for map reading.
Full regulation so it holds steady output.
18650 so good run time.
Have maybe 5 headlamps and this is the one I go back to time and time again.
$35 Amazon
Comes with 2600 battery but I use 3400 Panasonic for max runtime. Love it.
You should be feeling “eww;” caked on sweat not only stinks and tastes horrible, the salt destroys headbands.
Can you just picture the dripping from your forehead coming through the material and aggregating onto the work surface. This would truly suck.
Maybe it’s just me, but just like with a diving light that’s been soaking in saltwater, I’d just, like, wash it?