Also got a refund (they said they would in response to my PM query some days ago)
from Gearbest today.
Now I will refund their refund.
Aside from the slow shipping, it was a good retail experience, good customer service, good website.
Ordered mine with tracking number. One light, nothing else. I placed my order on the 7th of June and received it around the 25th of June, might have been up to 2 days before.
Tracking number was pointless as it was never updated, it stayed on pending the whole time and is probably still there…
Everything about the light is as stated by other members. I tried burning out the led but got bored so I swapped in my XM-L2 T5-6B1 on 20mm Noctigon, BLF17DD driver, and 22-17mm adapter ring from oshpark, courtesy of RED’s shared projects. Also using some leftover Arctic Silver 5 from my pc build.
Very happy with the light, and the heat-sinking it offers. The quality is very surprising to me for the price, everything is in very good order. Does not look like I payed so little.
It is a bit bulkier than I imagined, and it’s making me question if I like it more than my C8 clone. Also gets heavy with a 26650 cell.
It throws slightly less than my C8 with the flat around the emitter on the reflector, most likely since it is a slightly smaller diameter, but it’s a very little difference.
Shipping, quality and pricing, 9/10 would do again.
All I have left is to copper braid the tail spring, since it is fairly thin and quite long.
Ordered mine on 6/02 and still have not had it show up. wondering where my order is.
mine got here yesterday - it took 41 days
hoping mine shows up today or tomorrow, thanks for the reply.
Did the basic upgrade this morning
Solder braided both springs, put in a XM-L2 U2-4C on 20mm sinkpad, 22ga wire soldered before the resistor bridge, thing is CRAZY bright now!
Good news, I can’t wait to start on mine.
Do the move the emitter lead to the other pad thing - that should give you a good bump in current…
Sounds like he did 
yes, it removes the resistor bridge (thus making it full current out of the IC), plus soldering in 22ga wire vs the thin wire that was there didn’t hurt either 
Has anyone done any extensive / definitive testing on focusing this flashlight?
I removed the stock centering ring and replaced it with one from IOS. This left the guts loose, so I cut a paperboard ring for now (like from a cereal box) and placed that between the lens and reflector. One ring was enough to keep things from rattling, but I wouldn’t say that it made things tight. I’d do a thicker ring next time. I’m using a 20mm noctigon with 24AWG wire and had to move the wire to the outside of the solder pads to keep the reflector from shorting them. The hotspot is now much wider, but I’m not sure that it isn’t in focus.
Hopefully later I’ll take a little time with a light meter and see where focus is.
I haven't pulled the bezel and lens of mine but it looks like there is two o'rings in this area. One above and one below the lens. Could be wrong here though. If I had the same problem you had I was going to look here at adding a thicker oring. I did a bit of testing with different thickness isolators and took measurements along the way in my modded thread on this light. Good luck.
Still waiting. PP case filed.
Ordered 9 Jun, arrived today 23 Jul.
Stock current on high was a measly 1.7A. After spring braiding, changing to 20AWG wires and rewiring the LED+, the current went up to….2.2A? I guess my newly purchased meter is really shot… 
I am using a freshly-charged KK ICR by the way.
Make sure you’re using thick/short leads. That’s typically the key. DMM quality doesn’t have much to do with it.
got my f13 yesterday, have not had a chance to tear it down yet.
I'm not sure if its been reported but the last five I received on inspection had XML-2 leds. They also had XML-2 on the battery tube in place of the XML-T6. On a very quick test light output is similar so they must be a very low bin. When I have time I will look into it further.
Mine arrived a couple days ago. It also has an XM-L2 emitter, but the battery tube still says XM-L T6.
Hi .
I am willing to give 3A to my F13( with the OUT +1 trick ) but i cant have access to the driver and i would like some help ( im a noob ) .
Do i have to push hard 2 or 1 ? Is it ok to push it with a hammer+a screwdriver or a hammer+a spanner wrench, or should i buy something like this : https://www.fasttech.com/products/0/10002694/1200101-rewin-snap-ring-plier-with-4-changeable-tips to open it ? ( i have read someone did it with it )
I recommend using sturdy tweezers to turn the ring.