Man, their soldering jobs always scare me...lol. Look at the hole in the positive wire from the tool they used to hold the wire down while soldering. On many lights, you'll notice all the sharp cutouts that the wires pass through, with the wires pressed up against them. Just a short waiting to happen, and I wouldn't want that happening with an unprotected Li-Ion in there!
I'm not bashing the Kai and DealExtreme lights...I have many of them, and more on the way...but it's a good idea to inspect them and fix any issues, especially when using Li-Ions!