Bob Ross

My wife bought one of those for me several years ago. I will not deny that it indeed "works" ...i.e., you will almost assuredly "be seen"
I've had a number of people -- drivers, pedestrians, fellow cyclists -- pull up next to me and ask what it is and where I got it.

I would however add this caveat to your assertion that "You can wear it in any conditions with all types of clothing"
Yes, you can certainly wear it...but it is really effing uncomfortable unless you are dramatically underdressed for the current temps. The Tracer is way too hot to be practical.

Despite it consisting of mostly air -- plus a couple of thin plastic LED (or fiber optic?)-filled tubes, a fabric strap, and a plastic enclosure for the batteries and brains -- the fabric strap and plastic enclosure prevent any air circulation, sweat evaporation, or passive cooling, such that you overheat ridiculously quickly. The net effect is as if I'm wearing an entirely extra layer -- a heavy layer at that -- on my torso. So for winter riding, I have to forego the vest or jacket if I'm going to wear the Tracer harness. In the summer I have to forego a base layer...assuming it's even moderate enough temperature-wise to necessitate a base layer. If it's one of those hot humid short-sleeve-jersey-only summer nights, I can't wear the tracer at all (because I'm not gonna ride shirtless).

In short: Clever idea, crappy execution.