Good, but overall I prefer the Alpex - it has a wider FoV, more reliable automatic recording, and better video quality. My impression is there is also a bit more space for mounting an illuminator, but I may be wrong about that. Additionally, adjusting the dioptre ring on the Volans significantly increases the length of the scope (as per the Pard DS35), whereas the ring on the Alpex is more akin to that on a day scope (if that matters to you).
The pluses of the Volans are a modest reduction in size and weight (no internal battery), and (to me) a slightly more intuitive set of icons and menus.
Mostly nuances, therefore.
They're both worth having, but I'd hoped the Volans would be an advance on the Alpex, due to its coming on the scene later, but it's more like a bridge between the DS35 and the Alpex.
R.I.P. MJ