G9x.
Perfect number of buttons with perfect placement, durability, and feel
onboard memory
excellent well-shaped, well-textured grips (I use the super wide-load i-grip)
side scroll dual mode mouse wheel
5700 dpi/1000hz polling rate/no prediction laser (the accel issues with this sensor only occur on soft pads--I prefer hard); great macro functionality
on the fly dpi switching which can be bound to any key
not too heavy, not to light
durable, reliable overall build
I've tried many many well-reviewed mice and none have all of the above positives with such an absence of flaws.
Can't wait for the next iteration