TCI: thickness according to some measurements in a German forum: "5.6 mm, 5.7 mm, 5.2 mm, 5.3 mm, 5.7 mm, 5.0 mm" That's like day and night.
Donic Baum Esprit and Skachkov Carbon also use the Viscaria structure but have larger heads 159 mm x 152 mm afair.
DHS quality: It depends... with the...