TechPowerUp checked out the Mad Catz R.A.T. DWS
A quote from the article:
While it ushas almost the same shape and size as the wired R.A.T. 8+ ADV, the wireless R.A.T. DWS promises up to 200 hours of battery life, top-tier tracking thanks to PixArt's PAW3335 sensor, and particularly low-latency main button switches, along with several customization options.Mad Catz R.A.T. DWS Review