Looking to upgrade from a wired mouse to a wireless, I acquired the Logitech G403 to replace my SteelSeries Rival 300. The Logitech software (downloaded online) runs on Windows (10, 8.1, 8, and 7) and Mac (OS X 10.10.x or later), and I personally use it on both. For reference, I have the 27-inch iMac with Retina 5K display set to dual boot. Using Boot Camp, I load OS X for my graphic design work, and Windows 10 for gaming. I have found that the performance of the mouse is the same regardless of operating system. It even performs admirably in Parallels. However, there are a few missing features in the software for OS X (see below).For Graphic Design, in OS X, I use the Adobe Creative Suite, which includes programs such as Photoshop, Illustrator and InDesign. In the past I’ve had accuracy issues with wireless mice. For instance, when I’m dragging a marquee box there are times I need to move it by a single pixel. Other wireless mice I’ve owned shifted several pixels at a time so I couldn’t quite get it to the spot I wanted. Not so with the Logitech G403. It has pinpoint accuracy, letting me move the cursor one pixel at a time and without any choppiness (it's smooth). Because the resolution adjusts from 200 – 12,000 dpi, you can get even higher accuracy. But even at 3200 dpi, I feel comfortable dragging it without any slop or skipping or jumping.For Gaming, in Windows 10, I play a variety of types, from FPS like Overwatch to RTS like StarCraft 2. I find that the mouse’s reaction time in gaming is quite good for wireless. I experienced no lag or noticeable delays in movement, dragging, scrolling or button clicks. And as mentioned above, you can set the dpi to a wide range, lowering it to help with sniping or increasing it to gain faster movement. To switch between modes, you can do so by a quick click of a button near the scroll wheel.Should the battery die while the mouse is in use, you can plug in the included cord. This will charge the mouse while also connecting it to the computer, providing full control without the need for wireless. When switching between corded and un-corded, or even simply charging, the bad part of this is that the mouse ultimately takes up two USB ports. One for the cord (needed for charging and non-wireless play) and one for the wireless adapter. Had the mouse been designed to connect via Bluetooth, then no adapter would be needed (at least, for my setup), however Logitech used a different technology that requires you to use their own custom adapter (they claim this enables them to have more optimization, which seems to be the case). You could plug and unplug the two (cord and adapter) back and forth between one port, but that’s a pain. And personally, I would stay away from USB Hubs as that can impact the connection speed and responsiveness of the mouse. Ports in the motherboard (namely at the back of your desktop or side of your laptop) are ideal.Now there are some things I like better about my older SteelSeries Rival. Firstly, the Logitech G403 is wider than the Rival. I have a pretty large grip (big hands), so it’s not a deal breaker for me, but I do prefer a narrower grip. If you have small hands, it may very well be a deal breaker for you. Secondly, the sides of the G403 are smoother than the Rival. This means it’s more slippery and the friction does not grip my fingertips as well, so I feel like I have to squeeze the mouse tighter. Thirdly, the button clicks on the G403 are much louder than the Rival; that said, the scroll wheel is quieter and smoother to scroll with. Fourthly, there is a gap between the top buttons and the palm rest on the G403. The Rival has no gaps or seams on the top. However, I don’t find the gaps getting in my way; I never end up touching them, so it’s more of a visual preference than a physical annoyance.I measured the weight of the G403 at 107 grams vs. the 105 grams of the Rival. Very similar considering the G403 has to support a battery. Additionally, the G403 has an extra 10-gram weight you can put in at the bottom of the mouse to bring the total up to 117 grams. The majority of the weight on the G403 is at the front, so putting the added 10 grams on the back helps with balance. Personally, I like the ability to increase the weight, a feature I missed having when upgrading to the Rival from the Cyber Snipa CSLMSL01. (Note: For a weight comparison, a full can of soda pop is around 280 grams, which means that the G403, even fully weighted, is less than half that.)Because I switched from a wired to a wireless, the mouse no longer turns off when the computer shuts down. Thankfully, the G403 goes into sleep mode after a time so I don’t have to worry about the battery quickly draining if I forget to click the off switch at the bottom. You can also turn the lights off (scroll wheel light or icon at the palm rest or even both at once) in the Logitech software to help save on battery life. (Or if you like the lights, you can alternative lower the brightness to help extend the battery.) Logitech claims 22 hours of non-stop gaming with the lights on and 30 hours with the lights off. As far as I can tell, that is fairly accurate.Speaking of the software, it has a good amount of customization. You can set up three different profiles (good for switching between game types), change light color (and switch from solid, pulsing, or color cycle), view the battery life, tune the mouse to the surface of your mouse pad, update your firmware (for the mouse itself), assign new commands for each button, enter keystroke modifiers (for your keyboard), create keyboard macros, view “key press” heat map stats (shows which keys you press the most) and install Overwolf (a program that allows you to overlay your desktop and games with widgets). As mentioned above, there are some differences between the OS X and Windows version of the software. In OS X, you don’t get Overwolf (not supported) and you don’t have the Developer tab in settings (which allows you to launch ARX Console, LED Emulator and LCD Emulator). Other than that, as far as I can tell, everything else is available.Overall, I think the Logitech G403 is a good wireless solution for both Graphic Design and Gaming, and on either Windows or OS X. Good customization and responsiveness (my buddy even told me I was quicker when playing Overwatch). I just wish the mouse was narrower and had better gripping on the sides.PACKAGE CONTENTS:Gaming MouseCharging/data cableWireless USB adapterCable adapter10g optional weightUser documentation