I haven't followed anything here including conversation. But as long as I happened through, saw this post, and also happen to be an autobody repair tech, that has a couple friends that both teach and use this method of removing dents, so I thought I would read the PR and weigh in.
"Paintless dent repair"(PDR), which is what these lights are all about, is not an "as seen on TV" or fantasy gimmick. Although the lights are just one part of the process, PDR itself has actually been around for a couple decades and is a very real niche market which has become a rapidly growing industry to the point that almost every used car lot in any sizable community and also many body shops hire these skilled labor services(it's actually more of an art along the skill lines of pin-striping the side of a car with paint) on a regular basis if they don't have an in-house guy with the skill.
Although it doesn't replace a traditional body shop for bigger body work, think about it this way for a minute. If you could repair a parking lot door ding that didn't damage the paint, wouldn't it be better than 3 days in a body shop if you could remove the ding in 15 minutes or less without having to match the color and re-paint the door, and still charge $50-$75 retail for a 10-15 minute job that requires no additional materials?
This is where Paintless dent repair comes in, and as my friend has been doing this for the better part of 20 years, I have watched it evolve with his "practice"(yeah, its actually a little like being a chiropractor on a fender, except more precise and less aggressive than cracking bones), and most relevantly with the lights this company is talking about. The dent itself is actually gently pushed out from inside the panel little by little with any number of specially shaped long handled pry bars with a small rounded tip. The access points are mostly naturally occurring holes or slots in the panel like sliding a thin plastic protective sheet and going in between the window trim and glass in the case of a dinged door, removing a head or tail light and going through the tail light cavity to hit a ding in a fender or quarter panel and in extreme cases of limited access drilling a small hole somewhere that isn't visible to the general public and sealing it back with a rubber plug that looks as if it came from the factory as such, once the repair is complete.
If you crouch down to a little above eye level and look down the side or across the hood of your BMW with the correct lighting conditions(like later in the day with the sun in front of you on the horizon) you will notice the dings are more defined and easier to see if the paint is shiny. Hence, the function of the light(which actually replaced something called a reflection board when PDR was in it's technological infancy), it is used as an indicator to highlight the indentation as a reflection so you can visually see in and around the dent as a difference in reflection to monitor your progress. Back in the day, when all this started, it was a single company that figured out how to make it happen and did it behind a curtain at car shows as a trade secret. Once it out grew the veil of secrecy it was probably mostly done outside with PDR artists trolling shopping center parking lots or showing up at car shows or beaches for business, because one could just look around and see potential customers, and although many were skeptical at first, 50 bucks cash and done in 15 minutes on the spot with no time in a body shop is a pretty small price to erase the regret of parking next to a beat up pickup truck a week before.
Now it is an organized industry and even insurance claims utilize it.
Although I don't really keep up with the industry latest and greatest, this following history timeline of the "lighting evolution" is probably somewhat close. The reflection boards worked and probably still have their place, because they are compact and portable, but they also require an external light source and be positioned and angled just right to be effective. At some point PDR was discovered as a cost effective alternative to a complete paint job or writing off used cars as a total loss because the expense of a bumper to bumper paint job on a hail thrashed vehicle exceeded the repair threshold on many used vehicles.
In this type of production environment the reflection boards proved very inefficient from a time perspective because they were small and had to constantly be re-adjusted, and as LED lighting in general is a relatively new technology and not available then, that is probably about the time that it was discovered fluorescent lights were superior to the reflection board from an ease of use and efficiency standpoint since they provided their own light. So some companies that made PDR tools, started designing and offering fluorescent lights to replace the reflection boards, and although much more effective, what was available to the industry also required AC power, and as you had mentioned staring into a fluorescent light can definitely have a fatiguing factor.
Now that LEDs are mainstream, more affordable, very durable and very portable, they have actually been around the industry for several years now but are the latest in the PDR lighting evolution. And just as being someone with a mind for logic innovation, I'm guessing there is still probably some room for improvement in fine tuning the design of LED light sources for paintless dent repair.
Just as a fun fact point of interest comparative.. my buddy is actually what they refer to in the industry as a hail chaser, and since there is actually a hail season in some parts of the country, there are also phone apps built around alerting PDR artists to hail damaged areas and they flock there like migrating birds. My buddy is actually very good with high quality finish that unless you have a trained eye, you'd be hard pressed to see the repaired spot, and he is fast at it. Although the industry is rapidly expanding and big paydays are diminishing due to higher supply of artist with the same work demand, a good hail storm can usually make him $25-$35 grand or more for a months worth of effort, including the planning and travel time to get there and back. So with his only overhead expense being travel, lodging and the time away from his family, it is usually worth the trip. And depending on severity, if the vehicles have been pre-stripped; meaning the hood, deck lid and headliner removed/dropped by on sight skeleton crews, on average he can restore a car a day based on probably 200-300 hail dings Using the LEDs as backlighting. Assuming you are a hobbyist, I'm guessing, if you are roughing, filling, filing, feathering and priming, you would still be hard pressed to complete a panel a day.
If you want to see the technique in action, just go to youtube, For training they use a little magnetic ball to locate the ding with the tool, but If your bmw still has shiny paint on the hood or deck lid and you want to see how one can locate a ding from the inside by blindly sticking a rod with a hooked end into a panel, try this... first, with the hood up enough to reach your hand with pair of pliers under it at arms length. take a fluorescent shoplight and position it so it is sort of on it's side but back a couple feet away from the car and just high enough to stare you straight in the eyes when you are looking across the hood at just above eye level. If you did this correctly you should see a very broad "light" reflection being cast across the hood, almost like a small "pool of light". Now move side to side and up and down just a little as scan your eyes across the hood and you will see the pool move with your movement. Notice the hail dings and if the lamp is positioned correctly you will see the how the ding distorts the light compared to the rest of the surface, Now with the hood insulation off and your head still at eye level, take the handle of the pliers at arms length and applying a moderate pressure that is not enough to deform the sheet metal but enough to flex it a little look at the approximate location and drag the plier handle one way or another. If you did this correctly, you will see a "temporary" "high" spot that moves with your hand. So an artist stick his prybar in enough to get it close and then give a little pressure like that to find the edge of the ding, and then go to town on the ding, and with each tiny movement across the damage he gives it a little extra tweak pressure, but just enough to distort it back to pre-ding condition, but not enough to turn it into a high spot and keeps doing this moving it around on the underside of the ding until it disappears.
hope this helps and my time was of value here, as far as how all this pdr LED lighingh will equate to share price, or if they follow through with R/S, well at this moment, I'd say it is anyone's guess
AI
