The Cooper Zeon LTZ is a really nice tire. I had them in 275/55R20. They handled really well, nice ride, and looked great. I did get complaints from my wife about the hum at highway speeds though. I switched to the Michelin LTX MS2 in the same size. Not exactly an off road tire, but does just fine on the dirt and sand trails I need to travel. And they are just about silent, which keeps the wife, and me much happier.
I don't know about the 275/60. If you bend the pinch welds back and secure the felt, it might
work. I'm actually waiting to hear some reviews on the yet to be released Nitto TerraGrappler G2. If they are as quiet as they are supposed to be, I may try them out. Maybe in a 305/60R18...Not sure if it will fit, but just might try.