Yeah, the K60 won't drive in the red stuff. It'll last...yeah sure...but actually drive and brake...er..no.
The roads around the Snowy Mtns are mostly fine gravel on red clay. When these roads are wet the K60 was just like the Scorpion Trail. They were ok in the gravel I thought, but my wife on the back reckons the rear moved around a lot. I thought it moved around a little. She says she was shitting bricks most of the time on gravel and as a result she tensed up and all her back muscles would start going nuts.
Changed to E07 and she says it's much easier on her back. Weird.
I did make a tyre iron and groove out the K60s, they had roughly 10,000km on them and had 7mm out of 13 left at centre.
I put a couple thousand kms on them like this and they were heaps better on gravel. They started to sweat an oily residue just after I changed them. They'd been sitting in the sun for a week. They have a blue sheen on them now, and when it rains, an oily rainbow. Don't know why.