Regarding these lights getting cheaper. LED performance is going up continuously while their prices is coming down hard. Just like integrated circuits. The cost of the LED in that lamp is probably 10% of what it was 10 years ago when those first LED high performance flashlights came out. The LEDs are also more efficient, meaning more lumens per watt, so less battery power needed for the same amount of light and less cooling as well, so cheaper to build / package the assembly. Of course it is also made in China - all set $70!
G