I meant to reply to this thread earlier, but I forgot or something.
Anyway, I have an XO3 and a 4AA. My 4AA, despite Quickbeam's numbers and other various reports, does not out-throw my XO3. Lottery, I guess. The 4AA beam does have a VERY neutral white tint, which makes my XO3 look slightly yellow-green. Side by side the XO3 is appreciably brighter, at least in the hot spot, than the 4AA.
The 4AA, however, has a more useful beam, and overall output should be fairly close to the XO3. The corona is relatively narrow, but the spill is bright enough to be very useful when walking. The XO3 spill is very dim by comparison, but I find the big spot is better for medium-range spotting than narrower/dimmer spot from the 4AA.
Overall, I find myself going for the 4AA more often, because of the longer runtime and the more useful beam characteristics. It's a great deal for the price.
I'll post some beamshots in a second.
Okay, here we go. I am using a cheap camera now, as my "better" one broke just before Christmas. Please bear with me and try to ignore the noise.
Short distance:
Judging from the picture, it seems that the XO3 has more spill, but this is just reflected light. The camera does not open its aperture enough to capture the spill beam at this distance.
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Close-up:
Here you can see the beam profile of each light. The SL has a fairly bright corona, while the Inova has almost none.