Groove scrapers, slot scrapers, pipes, aerated concrete. Experiences?

Hello,

we will soon start building our house - with aerated concrete inside and outside.
My electrician usually works with prefabricated houses (but he is a friend and does not charge me) and I told him that I have already read on Ebay and other markets about so-called "Rillenkratzer Porenbeton Schlitzkratzer Leitungsschlitz Gasbeton", but found no experiences anywhere.

Would such a scraper really be enough to cut grooves for empty conduits, power cables, etc. into the wall with aerated concrete? That would be so convenient without a wall chase milling machine or chiseling otherwise.
Does anyone have tips or experiences regarding this?

"Enough" is what determines somehow how to get the groove into the wall. Whether he is still your friend afterwards? :P I think with this tool it is quite a hassle and takes a very long time.

You can probably borrow a wall groove router (I found several offers online immediately). That probably makes more sense and more fun...

So everything I have read so far about wall groove mills is that it is the smallest necessary evil, but still an evil. Everywhere people complain that these things are ultimately heavy, unwieldy, among other things. And since aerated concrete is relatively soft, I thought it was like using a sledgehammer to crack a nut, but I also cannot find any experience reports about these groove scrapers.