IMHO 219b 4500k would be a great gift. 519a 4500k has a warm/yellow tone that “normal” people may not appreciate.
China in yet another MAJOR lockdown so I am prepared if arrival of this light is delayed. https://www.cnn.com/2022/11/21/economy/guangzhou-china-renewed-lockdowns-guangzhou-markets-intl-hnk/index.html
I should note that S21D is a floody light, more useful for close range such as work around the house.
For an all around gift light that could be used around the house, and for camping, walks etc., and probably more in line with what “normal” people expect of a flashlight, I would recommend a GT-FC40 4500k light like the M21F wholeheartedly. Not necessarily my favorite M21E because E is more throwy and spill not as bright; F is more “balanced” between throw and spill. IMHO and hope this helps.
Would it be better to go with a hank light?
Not necessarily better, but definitely great and pretty alternate choice.
Multiple factors involved in deciding which light is “better”: host size, throw, output. Can’t help you much though as this is your decision to make.
Personally I prefer gift light to have integrated USB-C charging, and not all Hank lights have this. But again YMMV.
Does the stock lens on Hank Lights have AR coating?
Is it better for the sw45k 219b to have AR or without?
thx
Stock lenses on my Emisar’s do not have AR coating. That said the beam of D4V2 with 219b 4500k is equally as beautiful as S21D’s; the 2 look the same to my eyes. Duv actually measures nearly same.
Basically you can’t go wrong with either light. Some comparison numbers:
Duv
S21D ~ –0.0084
D4V2 ~ –0.0087
Basically both measure in the mid 80’s for Duv.
Throw
S21D 170 m with 10° Clear, 157 (10° Bead), 144 (30°), 113 (60°)
D4V2 137 m with Carlo 10622, 140 w/ 10621
If you want throw the S21D is better with the 10° clear TIR.
Output
About 1700 lm for both using Texas Ace Lumen Tube.
Sustained Brightness in favor of Convoy (that famous 37% at 10 min) at the expense of heat. I plan to do a comparison graph later when I’m not in lazy mood.
Size
S21D is larger so it has thermal mass advantage related to specific heat, but the smaller D4V2 feels GREAT in hands. The higher thermal mass (without battery S21D 4 oz, D4V2 2.7 oz) is important for sustained brightness and this and the longer throw of S21D with 10° TIR are the 2 main reasons I personally prefer S21D, but YMMV.
Drivers, Cosmetic, Cost, USB charging
Convoy has 8A Buck, D4V2/D4K has Boost option but that costs $12 extra.
Emisar is prettier to my eyes, with multiple choices for finish/color.
Emisar D4K with boost driver I think is about about twice the cost of the $30 Convoy S21D.
New Convoy will have integrated USB-C.
All IMHO/YMMV. You could do what I did and ordered both Emisar and Convoy. 
For the average person the coldest whitest light is best for the greatest wow effect.
Agreed, unfortunately. I only got a jump start as a result of rather excessive time spent with my other hobbies, photography and video. Still it took some time for me to learn about Duv and green monsters. Never forgot my puzzle with Cree 70.2 in a Thrunite light - wait is it normal for it to be so green .
Awesome!
Thanks for all the helpful tips guys.
Do you guys know if the S21D lens will fit on a hank light?
I got the stock carclo 10622 and was thinking maybe I should’ve got the 10623 or 10624
You are very welcome. S21D’s optics will not fit Emisar.
Are you trying to make your Emisar more floody with the frosted 10623? The negative side is it will reduce throw and make hotspot very dim. Subjectively in my Emisar D4V2 with E21a for example, it makes the hotspot subjectively too dim for my taste. Hank uses 10623 in D4V2 with E21a LED (not 219b) because E21a has a yellow tint shift that needs to be “hidden”/diffused with the frosted optic. (219b doesn’t need this because it doesn’t have that tint shift.)
For Emisar with 219b, for me, the 10622 is the “perfect” optic: beautiful beam, great balance between throw and flood. For more throw, 10621 only increases throw a little bit when I tested it. So basically if you want more throw, then S21D with 10° Clear is the choice. I posted throw and optic info for both S21D and Emisar D4V2 earlier:
S21D with 219b 4500K
1. Sofirn ~10° Clear 170 m
2. Convoy 10° Clear 170 m
3. Convoy 10° Bead 157 m
4. Convoy 30° Bead 144 m
5. Convoy 60° Bead 113 m
S21D with 519a 4500K
Convoy 10° Clear 157 m (using same optic, 519a less throwy than 219b)
Emisar D4V2 219b 4500K
Carlo 10621 Clear 140 m
Carlo 10622 Clear 137 m
Emisar D4V2 E21a 4500K
Carlo 10621 Clear 174 m (using same optic, E21a is more throwy than 219b)
Carlo 10622 Clear 170 m
Carlo 10623 Frosted 111 m (frosted optic makes hotspot of D4V2 w/ E21a very dim)
When the new S21D releases, what LED & CCT you going for?
Do you think the H2 headlamp is better than the H1? I see the H1 comes with a 75degree optic instead of clear for H2
10621 is more of a spot beam as opposed to a throwier beam than the 10622. 10622 gives a smaller, more concentrated hotspot, with a gradual taper to spill. 10622 gives a larger spot lit hotspot and minimal spill, however because the hotspot is wider, it’s not as focused. So it doesn’t surprise me the 10621 barely outthrows the 10622.
I wish carclo had something like a 30 degree beaded optic that hank could provide.
H2 is better for me because of my strong preference for USB-C charging. No experience with H1, but I LOVE everything about H2 as a walk light. Primarily because of its throwy beam (with good spill) and its sustained brightness (higher percentage of max than ANY other flashlights I’ve tested - check here). I have multiple headlamps, some expensive ones such as Fenix and Coast, and Convoy H2 with 219b 4500k is by far my most favorite. It’s heavy so you will need to have a headband with overhead strap. I could comment on some overhead straps (Olight, Skilhunt, Convoy) if you need to know.
For new S21D, most definitely 219b 4500k. With sideswitch and USB-C charging, I will use it a lot more than current S21D. I am not sure I would get 519a 4500k.
Beamshots of Emisar with various lenses. Test of optics (and Duv of Convoy green AR lenses) was the most fun :-), time consuming, and productive test on flashlight I’ve done. (My wife was very annoyed when I was doing this though.)
Any idea on the pricing of the new S21D? What do you think about the D4K as an alternative?
Sorry no idea on S21D’s cost. Simon’s modus operandi still seems to be great lights at cheapest price possible so I would guess $30.
D4K has different drivers (stock plus boost option) so output and runtime will be different from my D4V2, so no comment there. Use Anduril so stepdowns probably will take brightness to a lower level than Convoy’s 37% of max (my Anduril lights typically go to low 20%’s from Turbo start Convoy S21D w/ legendary Nichia 219b :) - Review & comparison w/ Nichia 519a, E21a & other LEDs & lights (D4V2, Convoy S21F). - #369 by cannga ), but the advantage is it will keep temp lower.
Seems to still be using Carlo Optic 1062x series (pls correct as needed) so same choice of TIR optics and beam should look similar to D4V2. For 219b 4500k I would still think 10622 is the most beautiful. It’s a great alternative to S21D.
For any Emisar fan like me lurking here, beamshots of Carlo optics 1062x series for D4V2.
BTW note the yellow tint shift of E21a; that’s why Hank uses frosted 10623 to diffuse/”hide” it. My test with TA lumen tube seems to indicate a 10% loss of light with it. For 219b 4500k personally I much prefer 10622 for a brighter central beam.
Such tint shift is also the reason when I use Opple Light Meter, I always make sure beam is perpendicular and Opple’s sensor lines up in 3D space with the center of the flashlight lens. Otherwise for example you may be measuring the tint shift instead of the central beam. These pictures took SO much time to do; can’t believe I did it. 
Hope it helps someone.
Thx for the beamshots! The 219b in the 10622 looks really good!
8A Buck driver use constant current regulation on all modes or some modes use PWM ?
Hi there, no PWM on any mode per my Opple meter.
Stay safe.
You’re very welcome. And actually in the adjacent beamshot with Carlo 10621, I could see some tint shift creeping in around the “corona” area. So yeah for D4V2 I think no reason to replace 10622.
what are your thoughts on the H2 as a Christmas gift? I don’t know if the new S21D will release in time