Well, I took the plunge. I will explain why I took the chance. Here is what I get for $400 (each for my wife and I):
1. A 700 Lumen light head that is extremely small, has a tight, bright 9 degree spot with a good, evenly lighted halo of about 50 degrees, with three intensity levels plus strobe, and, very rare, a lighted control switch on the head so no fumbling for the canister. Watershot says it is brighter than 10W HIDs and the Scubalab tests confirm this
2. A very nice "cut above" neoprene hand/wrist mount for the head, that has a hard plastic plate (padded underneath) and two straps (wrist/palm) so the light is very solidly mounted, I doubt I will even feel the light on my hand and will have total "hands free" operation.
3. An 8 cell Li-ion battery in a "canister" that gives six hours of burn on high and is so small and light I hesitate to even call it a canister. I doubt I will even feel it on my harness.
4. A 22" coiled cord instead of the 30" straight that is standard, making it more compact and less obtrusive.
5. A charger (of course) that charges the pack in about 5 hours (but recall this is a pack that gives 6 hours on high).
This feature set would be hard to find in any light, and reasonably priced at $800. To get TWO for this price is unheard of (and I have been looking for a long time).
If you want to save and only pay $300 each, you can chose the smaller Li-ion battery (4 cells, three hours of burn on high, 2.5 hour charge time). This is so tiny they even offer an "armband" stretchy neoprene mount and a 12" cord so there is absolutely no entanglement possibility, but still full "hands free" operation with a tiny light head (as opposed to a hand-mounted self-contained flashlight style light which would have to be large and heavy to equal this output).
Either of these would be an ultimate "travel" set-up due to the very tiny size and light weight. However, I do not see where they are lacking anything and are fine for a full-blown primary, even technical, dive light. i suggested to Watershot that they develop a battery pack that takes AAs and I think they might offer that next year.
Another good feature, the system is modular. Watershot makes another head with a 14 degree spot and a brighter diffused halo, and also makes a 75 degree video light head with the same 700 lumen output but a very even wide spread. They are freely swappable. The 14 degree head, I believe, would be a little better for general night diving than the 9 degree, but I went with the more penetrating beam and, instead, I also ordered two of the video heads so that when I am doing video dives, my wife and I can swap the heads and bring to bear 1400 lumens of light for videos. Plenty for most night dives, and useful even for daytime diving if you are close to your subject. Also, they light up a huge area and so are perfect for night dives in clear water. We also have the option of swapping to the standard head and getting the bright high-penetration beam for day dives or for clear signalling.
What sealed the deal was the responsiveness of Jonathan, their rep. When I asked for beam spread photos, he took beam shots of all three heads (9, 14, 75 degree) in his yard and on the wall of their warehouse. He answered every question I had very thoroughly and always within the same day. This seems to be a company that is serious about their product.
These will arrive probably Monday (free shipping to Florida!!) and we will be diving these on the 29th and 30th for a night/early morning dive at the Blue Heron Bridge. I will give my preliminary review then.
The 2 for 1 sale expires at the end of July. Maybe they will keep it going a little longer as more people buy and review these, but that is just a guess. I went ahead and invested my hard-earned $$$ in these but feel that I could not have touched this level of lighting quality otherwise.