Hola Pedro y Daniel. By now you know what your GS is capable of (or what you are capable of doing in your GS). If you're thinking of avoiding pavement, go with the lighter bike. My choice would be the DRZ400 or DR650 as they are arguably better on dirt than the KLR. If you were to do the trip in different legs you could use different bikes as the typical roads in all the places you want to go through vary greatly. As Colombians we can relate very easily to imagining a luxury bike in certain parts of the world and immediately feel unsafe. I'd consider that. Mucha suerte con el proyecto!!!