First of all, the marketing is misleading as without the aid of AIO support, this case is going nowhere in terms of being "ready for Intel 8-core" like the page claims. One point off for ridiculous claims that aren't remotely true. Fitting a 5820K is different from running a 5820K on a stock / maximum of something like 45mm height air cooler.
Secondly, 230 euros is absurd. The tried-and-true Ncase M1 runs for $185 USD.
And no, ~5L difference between the M1 and the A4 is not a hell of a big deal. If one is experienced enough to be dragging a desktop around on a regular basis, it can be expected that one has devised a workable, effective form of protection for the larger case anyways. At 7L, if you want to fit anything decent enough in terms of both CPU and GPU power, you are going to have to deal with uncomfortable temperatures, as the Dan A4 appears to lack effective cooling in the form of fans that aren't already attached to components; at that point.
I can see this case working for lower-power builds, but there are two issues with that:
1) 230 euros is absurd; it's Caselabs pricing for much less than Caselabs quality. Knowing how generations of the M1 have worked out, this case is not going to get remotely close to $100.
2) Low power builds don't cost a lot of money. By building with this, one will have defeated the purpose building such a low-power rig in the first place. Again, it goes back to the SG05 and M1, and we'll take the SG05 as an example:
Is it really so logical to spend an extra $210 just to save 3L of space and get some thin aluminum rather than SECC steel? And is it so logical to spend $60 extra just to get something that looks arguably less attractive and 5L more compact in the SFF space, while sacrificing nearly all options when it comes to cooling?
I've liked the A4 concept from the start, but I was not without my reservations. The pricing just confirms that this is a far less thought out concept than I first guessed.