I reckon pr4 is a good choice for mileage and awesome grip wet and dry. K60 is a horrible tyre and I gave mine away at 50% wear. Rough, lumpy, poor wet grip, wears flat on the back and cups on the front. Only mediocre on dirt and gravel. They do seem to last a while though so if comfort, grip, usability performance don't matter, the k60 is perfect. Except for the cost of course. Over priced and difficult to fit because of very stiff side walls. Forgot to mention those details.