I have the 4AA 7LED and like it a lot. When I bought it I had an email conversation with Streamlight about how the old and new versions differed. I am exerpting from the replies I got to post the following information:
"The first units had 12 ohm resistors in series with the LEDs (7 resistors, one for each LED). The 12 ohm resistors, visible through the opening in the side, are color coded BROWN, RED, BLACK, GOLD.
There was then an interim fix which added a large one ohm resistor to the back of the housing.
The current production assemblies do not have the external resistor and the internal ones have been changed to 22 ohms. These are color coded RED, RED, BLACK, GOLD.
You can probably identify which assembly you have by looking at the color codes on the resistors. Unfortunately there isn't a whole lot of visible difference between the shade of brown used in the old ones and the new red, so you need to take a really good look.
There is little to no apparent difference in intensity of any of the three versions. LEDs unfortunately have a very large range in the amount of current they draw as part of their normal manufacturing process, and the original values were chosen using LEDs of the lower current end of the range. This caused the ones that drew higher current
to be driven too hard. They not only were failing because of heat, but were no brighter than ones operating correctly.
If operated continuously, it is normal for the 4AA LED to get just as warm as the Xenon version when the batteries are fresh. If you do have any problems, please contact us; we have a very good warranty policy on our products."
"To answer your actual question, it's a much better product with the new resistor value. On the curve I'm attaching, the old value starts at 120 mils per LED and the bottom drops out of the cells at about 5-1/2 hours,
after which you get that anemic LED run forever time.
With the new value, it starts at 90 mils (you can't tell the difference in output because at 120 the LEDs were saturated and perhaps even backing off in output) and goes down smoothly. The curves cross at 4-1/4 hours and after that the lower value gives more output for a LONG
time. We didn't bother to do an actual end of life run with the new value, just kept the original claim.
There's so much variation in the LEDs, along with different makes or production dates of alkaline batteries, that it's really impossible to give an accurate end of run time figure. They actually run a lot longer than whatever our claim is. At the end of our claimed run time you can still read a newspaper at arms length or see your shoes well enough not to trip over obstacles in your path.
There's maybe a 20 mil difference in the actual current the LEDs draw. The graph is close to worst case (hottest). Some of the 12 ohm assemblies (like the ones we tested before we started shipping them!) are close to the 22 ohm curve and work well."
I don't have the facility to attach the graph they sent. I can email it to anyone who is interested............. Anyway, a very good light!
