Got this thing in the mail because of a little FastTech mistake with my penultimate order, my fellows.

Bits & beavers summary.-

The plastic headpiece has a sort of reflector type insert. After my first disassembly to put batteries (4 × AAA) inside, I couldn't place the head back over because the reflector insert had rotated a bit, and it was a bit stiff. I resolved by removing such @#$% with needle-nose pliers.
The output of standard 5mm white leds is quite tight, nothing to gain with such a high sitting crappy reflector.

Article picture from the product page. For reference.

With regards to the front plastic lens with slight recesses at each led position, another waste of time quite frankly. A single flat plastic lens and no reflector would have been smarter, avoiding any sort of beam corruption (very slight defocusing caused by the lens). There's some side light spill because of the headpiece base translucent ring.
Very simple driver board, long leaded emitters attached in a quincunx pattern and wired in parallel. Small integrated microcontroller unit under a white silicone bead, with an incoming red/blue wire pair for power and an outgoing blue/blue wire pair for an onboard momentary switch. Two modes: ON and 2Hz bike flasher (50% duty cycle). Mode cycle: ON/flasher/OFF.

Driver input current measured at ≈200mA. This is actually nice because AAA alkalines can't really handle more current (they already lose a slight capacity at such rate) and there's barely any cooling/heat-path. The use of 4 cells in series is actually thought-out, as with alkalines voltage drops quickly as they discharge; this allows to fully drain the cells after the driver goes out of regulation and drops the output (carry a 4-pack spare if unsure, there will be very little time remaining once you realize the beam is dimming). Vf reading came out as 3.25V after a slight 30 second warm-up. This in essence means approximately 0.65W of power at the emitters, something which makes the 50 lumens output claim very plausible, maybe a little more.
Estimated continuous runtime: 3½ to 4½ hours.

May add a nighttime beamshot if I do recall.