ᐅ Decentralized Ventilation System: Which Manufacturer?

Hello everyone,
I am planning to retrofit a decentralized ventilation system. Are there any positive experiences with this?
Which manufacturer would you recommend? There are many options on the market, but it is very difficult to judge what is good.

I would appreciate any suggestions. It’s hard to know where to start.

I am also considering whether to choose devices from Suedwind in Italy or from the Raumluft-Shop dot DE, the Rücklauf 50 RAS. With the latter, you even get calculations and installation suggestions, etc.

Can someone explain how well a corner installation using the window reveal works with an external thermal insulation composite system (ETICS) / insulated facade?

I will install the inverter with the new wireless module myself during the new build.

@NoggerLoger
Could you please tell me the exact models you are using for this and how you control them? According to my research, it is actually only possible to control them smartly with Easy Connect or the HUB.

In January 2020, I purchased a ventilation system Return 50RAS Allergy Set. The delivery was quick.
However, the device vibrates in its natural frequency, but only in one direction, and makes noise. Despite multiple inquiries I have sent since February 2020, I have received no response as of today (June 14, 2020). They only focus on sales! Anyone expecting customer service should stay away.