Nope, never heard of them.
There is some solid science in their technical articles and some total nonsense which shows a lack of understanding of basic low frequency acoustics. Overall, this is a better version of the Velodyne feedback model which reduces THD, but still has issues - like peak output at low frequencies and artifacts. I have always disliked Velodyne and I have no reason to believe this company will be a true replacement to a properly designed, build, and sized traditional subwoofer. That said, using their "direct servo" kits to make a properly designed sub could be VERY interesting - like using these to make an IB sub.
I haven't heard these, so I cannot offer a proper opinion, just speculate based on experience, knowledge, and science.