We're back from Bonaire (unfortunately
) and the light performed flawlessly. I took it with me on seven dives, day and night. Max depth was 110' fsw, never a hint of a leak.
There was definitely better penetration with the MT-4 Maglite than the Miniwave. The hot spot would pierce dark water maybe 75'? (Daytime vis was at least 80'). This was my first night dive, and it's hard for me to judge distance underwater at night. We dove a double reef in the afternoon, then went back to the same site that night. There was about 150' - 200' between the reefs, and swimming out to the second reef I figured the MT-4 started picking up the reef about half way across. For close up, though, the hot spot was distracting, just wasn't the even beam pattern of the Miniwave.
In daylight, the Miniwave gets washed out, but the hot spot of the Maglite still lit things up to show more color. It was also great for lighting up holes from a distance, so I didn't have to swim over to get a close look to see if something was in there. It also did a much better job penetrating deep inside the Hilma Hooker, a 235' cargo ship sitting @100' depth.
At night, I used the MT-4 on power level two for most of the time, only occasionally turning it up to level four, like when crossing between the reefs. Otherwise, level four was too intense for close viewing.
An explanation of the attached pics:
Pic #1 is a daytime shot with the camera flash disabled, showing the hot spot in full sunlit 80' plus visibility.
#2 is a blurry night shot with the camera's flash disabled; the hotspot is about 15-20 feet away @ power level 4.
Pics 3-6 are night shots taken with a compact point-and-shoot Cannon 550SD and no external strobe. The internal flash was enough to wash out the MT-4 hot spot (power level two), and the camera, of course, needed the Maglite to focus.
Overall, I'm pretty happy with the modified Maglite. I kept it clipped to my BC with an Aries retractor. It is bulky; the Miniwave wins hands down for size. One of the reasons I built the MT-4 Maglite is now I keep it in my truck; it makes a great tactical light. Thanks again to all who gave me tips on this project. Now I have to start planning a trip back to Bonaire...