It's ironic that so much effort has been put into getting headphone sound OUT of your head, and at least in a marketing sense, these guys want to put it IN your head.
If the tech really works, as to sound quality and perfect head tracking, then it needs to be married with tech like SMYTH realiser A16 such that it perfectly sounds like you are in a 3D immersive sound environment. They mention 3D, but it is in conflict with that "in your head" stuff.
Also I wonder about the tracking. What can you really do? I don't think you could turn 90 degrees from the unit, or walk away, or move freely around a room?
One of the things that is not (yet) in the realiser is 6 degrees of freedom, where things get louder, quieter as you move further away, or closer to them. It would be cool if this tech did that. You get that in VR today.