(German version) Beschreibung und Kaufempfehlung: BMW 650 GS DAKAR oder 650 GS SERTAO ?

As mentioned, here's the travel blog on the topic: www.frankbordtfeld3.blogspot.com ...after now owning five BMW F 650 GS DAKARs and two BMW G 650 GS Sertaos, I'll draw a conclusion, explain the differences, and make a recommendation. Which bike is better for you: DAKAR or SERTAO?