I have no opinion regarding the quality of ADV.1 wheels. I have noticed that they do seem to be popular. The main issue that I've seen in this thread is that they said they had TUV certifications and then said they would post one. They posted something titled as a "Certificate of Conformity." If that's not an actual TUV certification, then (in my opinion) it brings into doubt whether ADV.1 has certifications and knows what they're talking about. Also, a picture standing in a TUV facility is no proof you're certified; it only refutes claims that "TUV has never heard of us."
I used to perform ISO 9001 audits of organizations and, as such, I always wanted to see proof or evidence of something. People frequently make careless mistakes (or try to answer questions they shouldn't be trying to answer) when audited or pressed for information. The posting of a "Certificate of Conformity" (instead of a TUV certificate) may be one of those types of mistakes. In my audit situations, a simple "oops, my mistake" would suffice (followed by the correct proof, evidence, or explanation) and no negative consequences would result. I believe that's all we're asking for here.