Pros: Good quality, holds the charge well and works perfectly. I use it with my UltraFire C3 Cree Flashlight (sku 01993).
The circuit cuts off the discharge when the battery is flat, so you know when you have to recharge it.
Good price!

Cons: A little bit bigger than regular AA batteries (because of the circuit), but it fit well my flashlight.

Other Thoughts: I recharge it with my Universal Smart Quick Charger (sku 14885). It recharges really fast!

Bottomline: These are the first rechargeable batteries I bought on DealExtreme and I'm very pleased!

Pros: Finally, my first protected cells arrived. Measured 3.84V which is good. After charging with the 'OEM charger" (100% fully charged and went to discharge test...
The capacity is 857 mAH which is good since I expect less as experienced from previous 'fires'.
The battery cut off @ 2.65V and remained so until the load was disconnected as expected.
Perfact. I do not have to worry about discharged to zero voltge wich generally kills Li-on cell.
Note: Sku 13820 type of charger stays at 4.24 Volt and truely 'tops up" the battery. The DSD type cuts off @ 4.28, usually means internally the Li-on cells ia about 4.0 V meaning only 85% charged due to internal resistance. You can tell by measuring the terminal voltage immediately after charging.

Cons: The one bid disadvantage is the length is now 51.8 mm instead of 50 mm.
This is big deal because it is too long for "AA" size. In my case, I have to modified my battery cap.... not I wanted.

Other Thoughts:

Bottomline: Since this "AA" size lithium cell generally is to replace 2 "AA" size in flash light, is a matter of adjusting spacer. In the even the cells are arranged side by side as in radio or camera, this oversized "AA" wouldn't fit at all..

Pros: These batteries are great. They hold a charge well. Decent runtimes. Great overall batteries. I would defiantly pick up more of these in the future. Very nice.

Cons: Nothing I can see, Build quality maybe but hey they are 5$ a pack of two! Cant go wrong here. Shipping times but what do you expect from DX?

Other Thoughts: Very cool product. I use WF-139 Ultrafire charger.

Bottomline: This is a buy. Defiantly pick them up. I use these in my Nitecore D10. Fenix AA lights. Energizer lights. They are great I love them. Will not work in just any AA electronics but will work in most flashlights. Works in Eagle-Tac P10A and there 2xAA series of lights. Will work with Nitecore D10. Most Fenix lights. Romisen AA models should work with this as well. This is a great deal here folks. Love it!

Pros: Reasonable price.
Fits well in AA/14500 flashlights.
Decent over-discharge and over-charge protection. Both cells cut off charge at 4.21V while one tripped discharge protection at 2.65V and the other 2.62V (~350mA draw).

Cons: Actual capacity is a bit lower than rated. Drawing 350mA gets just a few minutes over 2 hours out of a cell, which puts actual capacity closer to 700mAh.

Other Thoughts: The cells are just a hair taller than AAs thanks to the PCB, but they still fit quite nicely in AA/14500 lights.
The bump in the shrink wrap at the positive node from the PCB strip on one of my cells is unusually pronounced. A really tight holder might wear on that, so it's something to keep in mind if you get a cell in similar condition.

Bottomline: Not a bad battery at all for juicing up your EDC light with more voltage (provided it'll take a 14500 anyway).