Oh, I agree there are differences in beams. For example, the Hotshot will appear to be much brighter if you are straight on to the LED (narrow beam). The vis180 is much broader - but that's part of the problem.
A couple of comments:
1. Beamshots are deceptive at best due to the nature of digital photography. The camera cannot see the range from dark to light that the human eye can (i.e. dynamic range). The dynamic range of the eye is something like 20 doublings (f-stops) of light. A digital camera is 6-7 or so. That means that the gradation of the beam will not show up well in a photo. Therefore, for example, I'd conjecture that the Cygolite Hotshot will have much more spill than is shown in the photo since it's got such an intensely hot spot in the center and that is more than the dynamic range of the camera to the darkest shadows. Light junkie that I am (and photographer), I've observed this numerous times with beam shots I've taken of lights. The subtleties of the light are really minimized or lost in a digital photo.
2. In general, lumens is the raw light that is projected out and lux is the light per square area. So if I had 50 lumens and sprayed that over a 50 square meter area evenly, I'd have 1/50th of the light output in each square meter. The more you spread it out, the dimmer it will appear. Conversely if you want to have more lux then you need to throw a lot more lumens at it. Lights that aim the photons where they will be seen, and nowhere else, do a the best job. An example of a light that is visible and bright from all directions is the Nightzone 8 (and almost taking the point to an extreme) which has a 300 degree viewing angle but puts out an incredible 400 lumens in flash mode. If you did the same thing with a 50 lumen light, you'd not have much.
And that's where I think the vis180 is deficient. It's lumen count is too low (or at least marginal) at 50 lumens for the spread of the beam. I think it's a good light but for what it does, it's overpriced but it is a 2 years ago light. I'm hoping they update it with a 100 lumen output (or greater) then it will be state of the art light again. Just need to update those LED and their drive and a bit more battery in order to justify the $100 price tag. Otherwise, against current 2014 lights, it needs to be at about a $50 price point.
What is important for max safety is to get to enough lumens that it causes vehicle driver behavior to change. All quantitative of course, but I think that happens at about 100 lumens with about a 30-40 degree beam (maybe up to 60 degree). I have not seen it happen with the brightest of the blinkie lights but I have seen it with about were the Dinotte 140R starts (whatever it's beam angle and lumens are). Looking at it that way (and way over analyzing it, of course) is that one would want to put in the minimum dollars to achieve the behavior change as maximizing their light dollars against safety.
J.