Let me chime in for tires.
Bought lately two METZELER tires for my Yager 200i on internet from a German seller. Front 130/70/12, rear 140/70/12.
Both were produced 2020. Went with both to my scooter shop to have them changed and this METZELER mounted and balanced. It came out that, both rubbers had a vertical inbalance of appr. five to seven millimeters, which we were not able to equalize. They litterally jumped on this balancer. Seemed to be a fabrication failure.
Laterally they ran perfectely. The tire- guy checked both rims for imbalance, nothing. So I ended up to take a pair of CityGrips from this shop, and to dispose both brandnew METZELERs.
My lesson learned is now, buy tires where they mount them. So you can easily complain and claim immedeately a change.