Bluetooth is an excellent technology, overall. But, it's not without its flaws. For most of its lifespan, a major one flaw has been its susceptibility to latency. This refers to a lag time between a user or device issuing a command and that command being completed on the other end of the wireless connection. If you've ever noticed the audio in your Bluetooth wireless earbuds is just slightly behind the visuals of the video you're watching, that was latency rearing its ugly head. This delay is fairly minor, often less than 200 milliseconds. But, when it's consistently applied to every movement of your mouse, every click…it can be quite annoying. For gamers, it's often completely unacceptable. That's why most gaming mice and even many productivity mice rely on RF-based dongles, even if Bluetooth is available as an optional, secondary connection method.These USB receivers work over a different frequency than Bluetooth to prevent interference with Bluetooth devices, and they are purpose-built to reduce latency to the minimum possible. Some of the best RF receivers have so little latency they match their wired counterparts on a 1:1 basis for responsiveness. If you're not bothered by the minimal delay offered by Bluetooth, then, by all means, continue to enjoy the benefits of near-universal connectivity and easy setup it provides. But, if you prefer the best feeling mousing experience, you might have to put up with one more USB adapter.