Camparing the various chinese power supplies I ended up with Sunny brand, that is represented in Europe by a reputable firm. https://en.sunny-group.com

Opening one of them reveals that the design is in pretty good level.

Please be very carefull with all these cheap SMPS that are sold at low prices. They can have really catastrophic failures (I was almost hurt by this), with very bad "protection" circuits that fail after the big-bang...!

The idea of having a 5V wall adapter may seem good but there is a risk that the user may by mistake connect a 12V adapter at the 5V entry...

Ioannis