I think Wolfman Expedition bags are a good choice. I have always liked Wolfman products.
You might ask the Wolfman if his rack is more narrow than the KTM rack. I think it is. If it is, I would go with the full Wolfman system. Its more narrow and the bags will be better secured IMO. A narrower setup would be much better for all the filtering in heavy traffic. The KTM rack itself is a bit wide. However, You could have issues with the more narrow wolfman rack because of your aux tank, not sure though. You are riding in Latin America correct?