I've had two sets each of both TKC80 and Mefo on my old 950A. In my gentle hands, the TKC rear lasted about 3k miles and the front just under 7k miles. The Mefo's lasted 7200 miles at both ends and were totally finished.
I think the Mefo's rode similar to the Scorpions. Quiet with similar grip wet or dry on tarmac. On dirt roads that were dry and full of babyheads, the Mefo front was very good. In mud it was terrible. The Mefo rear was very good all around and lasted so long. Meanwhile the TKC front tire was by far a better dirt tire wet or dry. I found TKC 80's to be poor on wet and cold tarmac. Plus the TKC front was unstable above 90mph.
If I was on a trip and expected to be riding dirt roads, my choice would be a Mefo Super Explorer rear tire with a TKC80 or Pirelli MT21 front tire. If I had no dirt planned I'd opt for the Mefo or Pirelli Scorpions at both ends.
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