It's also expensive.
Can't say I like / dislike Razer's software more than alternatives - either the software is designed to support a narrow range of peripherals, as most smaller manufacturers do, or you go full Razelogicair and have something that looks and feels bloated for just a mouse (or keyboard or whatever).
But back to price - I can see it being worth US$150 if it had excellent longevity. My only real complaint is that it has a) no wireless charging option and b) no 'dock' for charging. This isn't a complaint I have with cheaper wireless mice, but it's something that I'd like to see for 'gaming-oriented' wireless peripherals, not just for mice, but headsets too.