The Logitech G502 was your choice for best gaming mouse (though you don’t need to be a gamer to appreciate its benefits), and the upgraded Proteus Spectrum model (which includes fully adjustable backlighting) is on sale for an all-time low $52 today, the best price of 2017.
The marquee spec here is the DPI range of 200-12,000, adjustable on the fly. There are also five easily movable and removable weights, and 11 customizable buttons, along with the classic Logitech dual-mode scroll wheel. Mechanical microswitches and a braided cable are also nice touches.