I have been doing in town commuting since I'm restricted to city streets. I did hop on the highway for a couple of miles with a buddy, took a peek in the tank today with ~130 miles on the trip meter. Tank appeared to be more than half full, and I normally cruise between 3000-4000rpm at the most. That's a good sign to me.
I bought the thing for commuting, so if it's giving me these numbers then I'm satisfied.
My KLR is my therapy session. My quiet time. My deep tissue massage. Me without my KLR is reason enough to be deeply concerned. It is what calms me the most. Soothes my mind. Eases my stress. -Me