Picked up the Shimano SM-RT64-S for my trail bike and it's been a solid upgrade. Braking feels powerful and consistent, and the Center Lock spine mount plus lock ring made installation quick with no rotor bolts to fiddle with. It works fine with both resin and metal pads, so I can swap as conditions change. The included external type lockring is a nice touch. Good value rotor if you want dependable stopping power without overthinking it.