Having not heard any Bone Conduction and people struggle to express how to explain the effect, like you all have a good go at this but everyone finishes with "but i don't know, it is hard to describe". Then i had an epiphany moment, a lot of audio descriptions translate over into photography and video, so lets say something like this...
If the Aten is like a 24" 1080 16 x 9 monitor
then the PB1 is like a 34" 1440 16 x 9 monitor
then Semper is like a 34" 1800R curved ultrawide 21 x 9 monitor
then the Astra is like a 49" 1000R curved super ultra wide 32 x 9 monitor
So the Bone conduction offers that level of immersion of a 49" 1000R curved monitor, maybe but i don't know it is hard to describe not hearing them yet nor seeing that kind of monitor, but after taking in and processing all y'alls impressions and trying to get a feel for what that must be like this was the best analogy i could come up with.