The answer is simple; both, I mean all three. I've got an r100gspd for long trips that are on road, mellow two-track and gravel roads. The 650 Dakar is for medium length trips that have routes with on road, gravel, two- track, rocky terrain, and minimal single track. My new custom built 2014 KTM 150/200 xc is ready and waiting for me to come sign the paperwork and bring it home. It will be my singletrack assault weapon!
Every bike has it's benefits and drawbacks. If I were going around the world I would take the f650 Dakar if I had to choose from the bikes in my garage now. If I could take any bike at all it would be a well accessorized dr650.