I don't know if it's appropriate to answer in that thread as I am considered a competitor, but since my product has been mentioned above I'll write my honest thoughts.
I've been working in-depth with crystals for over a year, I saw in person almost every procedure done in order for sapphire crystals to be manufactured. I've seen in person the cutting of rough corundum/sapphire, giving them shape and polish in order to appear as watch crystals, I have discussed with experts about the magnification effect and how it is achieved. I have discussed about AR applications, durability and other parameters, I even been in a lab while applying the AR coating on lenses.
I am not going to say my personal opinion on the above product ( I did in private with OP, who also asked me to post my thoughts here), but I am going to post about AR crystals in general.
My personal suggestion to everybody interested in buying such a crystal is first to question themselves for what are they looking for. Are they looking for the cheapest available option? Are they looking for the clearest AR? Are they looking for gen-spec crystals?
What you have to consider is that you have to see a review out of an independent reviewer who will have all available crystals, under the same light conditions and will shoot pictures from multiple angles.
After that you have to consider that a crystal is not only the AR coating, actually it's the exact opposite, literally AR coating doesn't even consist 1% of the crystal. The shape of the crystal matters a lot, not only for gen spec appearance but also for light distribution, that "rolex bling" which every rep crystal lack. That has nothing to do with AR. Every other crystal I've seen so far is "just another crystal with AR coating applied"
It's really great having a lot of options but what I am going to suggest is to wait to see all the available options and evaluate them. Prices mentioned in above posts may not apply to "non prototype" products so give it some time to see them in person.
If anyone needs my personal opinion about the product advertised above feel free to send me a PM.
Oh bellow I am attaching a non-AR tc crystal to show you that the black hole effect can be present even with non-AR crystal at specific light conditions/angles. That's why I said I above you have to wait for an independent review.
For people in the business it's really not the best thing to have much competition, but for the average "consumer" it's amazing. 2017 is going to be amazing for rolex modding.
Regards
Asmo