The K-Swiss Ultrascendor II. I've been playing in the them since the summer. They've performed as well as any of the more expensive shoes I've worn. Asics, Nike, Addidas, even the original Ultrascendor. It's also one of the few shoes I've tried that truly are court ready out of the box.
I don't drag my feet around the court like Nadal either, so I don't need much of the these durability technologies on the more expensive shoes.