SC52, I’d recommend that light to anyone.
if i have to do it all over again and only can have 1 light ?
i would definitely only get TK75 as it’s a good flooder and thrower.
that light will satisfy my lumen lust for sometime…
Olight S-10…tiny, got moonlight, makes headlamp with clip, 430 lumens without overheating on a 16340, magnet, all the green tint you’ll ever want, EDC Deluxe. This and a thrower and you should be covered.
xintd x3. four mode, and if I was choosing the emitter the hi cri 6a1.
Versatility of using 3aa for noobs and can then upgrade to li ion cells of they really want the hassle and can be trusted.
With no guidelines its difficult but I wouldn’t put li ion cells in just anyones hands tbh.
I don't want to join the CRI police, but the 6A1 from intl-outdoor is 80 CRI Minimum (80+ CRI)
High CRI equals 90+ as far as I am aware.
http://en.wikipedia.org/wiki/High_CRI_LED_Lighting
Edit:
One light, ZY-T11, aluminium reflector from ZY-T29, DrJones Lumodrv@ 2,8A or higher combined with XM-L2 T4 5B1 (80 CRI minimum) on copper. :)
I’m a sucker for a good bright AA light, so I would go with the Sunwayman D40A or maybe a Lumintop SD10 because I can use Li-ions when I want to.
yes, but I assumed we were discussing an off the shelf light, therefore I stick by my recommendation, and minimum 80cri is still much higher and more pleasant to use than say an xm-l u2 for arguments sake. 
Me too!
Me three! :D
It's seriously my favorite all around small light. I just ordered the SC52w recently despite already having the SC52.
The UI does take a bit of getting use to, but is pretty good. Only think I personally would prefer, is if it had mode memory, to turn on to the last mode you turned it off at, as opposed to always starting in low or high.
The preset programming is fine, and to change it, is a matter of minutes, and a bit of clicking.
Prolly the Olight SR51… love that light…
I would recommend the Balder HD-1, the version with XM-L T6 in tint 3C!
I own this light myself and it is astonishing bright on AA and goes really blinding at 14500 (even LiFePO4!), the tint is great for color reproduction!
Everyone seen it, would like to have one and for sure will keep it! 
Had the light, and sold it a while back. It can very easily overheat on a 14500.
Oh this one is easy to answer after spending $4000 (pocket change for many BLF members
) on this hobby and many long nights trying to find a great flashlight. I think I can finally answer this question without doubting myself...
For me the ONE flashlight that would stay in my collection if I had to sell them all about but one is my 6.5A ThruNite TN31 modded by vinhnguyen54.
Words cannot describe this light. It has a blinding hotspot that will reach out further than any LED light I've ever seen. It has great UI and a moonlight low. Stock the light is pretty nice but after this mod there are very few lights that can touch it. The only things I would change is remove 1 mode because there are too many and I wish the reflector was as shiny as my TK75. With those two things this light would be bordeline "perfect" and I rarely use that word to describe something.
Sure, but really, who needs this nearly insane amounts of light, this tiniest gadget throws out for long periods?
I normally use this light on middle, but if you need power you can get it.
Really: Where you can get this insane amount of light for longer times from such a little package without overheating - tell me please!
Greta, shush! I can do it myself without help. Quite, here they come.
Ah, some kind of Surefire.
I recently had a light come my way that I did not think would impress me as much as it has, to the point that I carry it every day at work and I’m trying to figure out if I can put tritium on it: the Spark SL6S-740NW with a T5 XM-L2 emitter. I had to use it in a cave, and this is how it looked:
For comparison this is what my Convoy M1 with a T4-7C emitter at 2.8 amps looked like:
And if anyone is interested in more Convoy comparisons, here is the S4 with a T6 4C at 2.8A:
And a Convoy C8 at 2.8A with a T5 5C:
NiteCore TM26
So many great options. I'd probably suggest a SWM D40a or the new XinTD X3 running eneloops. With no specified requirements I'd have to stick with the smaller lights for all around use and carry. Maybe a ZL SC52. Too hard for a flashaholic to list just one perfect light.
Sunwayman D40A. Its got most of the modes covered.
S6330.
Small size easy to carry around
Output cover from 0.09 lumens to 2400 lumens
Three independent circuits accepting 3 x 18650s