successor for the mx518 with 3600 dpi optical sensor, 1000hz and a "consistent response ratio":
"Physical mouse movements translate to the same amount of cursor movement irrespective of speed: <0.5% variance compared to 5+% for some other “gaming” sensors."

Technical Specifications

Tracking Resolution: 400–3600 dpi
Image processing: 5.8 megapixels/second
Max. acceleration: 25G*
Max. speed: 70–140* inches/second
USB data format: 16 bit/axis
USB report rate: 1000/second
Sleep mode: Disabled
Glide Dynamic coefficient of friction – µ (k): .09**
Static coefficient of friction – µ (s): .14*
Total weight: 133 grams
Cord: 15 grams
Durability Button life: 10 million clicks
Feet: 250 kilometers