Quick Note: I have had the mouse for about 4 days as of the time of writing, so do be sure to take that into account. Should anything change, I will try to come back and update my review accordingly. Also, there is a lot here, and probably more that I have missed, so just a heads up.Bonus note: Apparently the mouse comes with 6 months free unlimited online storage on Amazon Cloud Drive. It also seems to account for if you already have that by offering bonus time or refunds. Now, I must admit that I had trouble getting the order to ship, so there is a chance that Customer Support gave me that, but nowhere in the email does it say that, nor did the customer service rep. So, if you have already or plan to purchase this mouse, check your email! This email came a couple of hours before the email saying my order had shipped, but keep your eyes open just in case!-My First Impressions (Kind of a Tl;dr)This is a really nice mouse. I am coming from a Mad Catz R.A.T. 3 (which was really comfortable) and so far I am really impressed with the overall feel and look. I feel that it doesn't have the same "wow" factor the R.A.T 3 did (a lot of people asked if they could touch it), but it is still very nice, very presentable, and has its own unique charm to it. My personal favorite part is the sail on the palm rest, which I think looks a good bit better than the old design they have available. Overall, I really like what I have experienced so far and hope I have no problems with it.-Look and Feel (and grip) - Note: I THINK my hands are on the larger sideI have to say that I was worried about how the mouse would feel because my last one absolutely spoiled me, but I find it to be very comfortable for extended durations of use. It has little wings on the side to keep your thumb, pinky, and ring fingers from rubbing against your mat/desk/whatever. I find that the tips of my index and pinky still touch my mat occasionally, but it's not enough to cause any problems or discomfort while gaming or working. It could be a little longer, but I find that's a rather minor issue.Fingertip and Claw Grip (and large hand users): I believe it is advertised as a claw grip mouse, but I use somewhat of a hybrid between fingertip and claw (closer to claw, but with fingers at a lower angle and wrist further back) and have no issues. I tried to emulate both grips as best as I could, and I'd say that both should be fine. I could click the mouse buttons pretty rapidly and reach almost all the buttons with ease. With claw grip, I had a harder time reaching Button 8 (behind scroll wheel), and with fingertip, I had a hard time reaching Button 6 (next to "SAIR" imprint on left-click). I'll go into the buttons a more further down, but I wanted to give a heads up to you guys. To my large handed people, I won't say too much because I don't know how hand sizes really work or are measured, but I think you would be fine if you use these gripsPalm Grip (and large hand users): Since I don't use palm grip, I cannot say for certain how this mouse will perform for you, but when I tried it, it was definitely useable. It felt a little unnatural, but I was able to left and right click rather easily and rapidly. Button 4 (behind scroll wheel) is hard to get to, but every other button felt accessible. For those worried about Buttons 7 (next to left click without writing), don't. For some reason, it's a lot easier to click than 6. I could move my finger over both and easily press B7. B6 (next to writing) needs serious work. That one requires effort, but I'll discuss that later. Large handers, depending on how big your hand is, there may be finger overhang, but moving mine up and down the mouse didn't drastically effect click time or effort. Also, for palm-handers in general, most of the weight of my hand fell right near the knuckles, palm side, of index and middle finger. I don't know if that's normal, but I felt it was worth mentioning. All in all, I felt it was usable, but I think it'd be worth seeing if you can find one in a store that will let you try it out for yourself.-RGB LightingThis is my first RGB mouse, and I really like what they have done. The scroll wheel, palm rest, front side, and DPI indicator all light up, and all are customizable to your liking. As Carter's review mentioned, the front-side light isn't that bright at all. In fact, it's hardly noticeable unless you use a bright color like bright green or pink. All the other lights are very nice, however. Both the scroll wheel and palm rest are very bright, and the DPI indicator looks nice, but isn't distracting to the eye. As for the different types of lighting, you can have a Rainbow effect where the lights change randomly at 3 speeds, just a Solid Color, a Color Pulse where the lights fade in and out between two separate colors at 3 speeds, and a Color Shift, where the lights change directly between colors at two different speeds. NOTE: Color effects are for all but DPI Indicator light, that's just a solid color. But, the other three can have any of the four effects, separate or together. Really well done overall.Quick Note: Lighting is optional, and can be turned off.-DPI and Performance - Note: Go to this section to customize the DPI Indicator lightThere is a ton you can do here. This is the first mouse I've actually made custom profiles for (could do it on the R.A.T., but didn't use it), and the DPI customization is great! You can have up to five different settings, but they give you the ability to enable or disable them however you please (I use two atm), and set which one you want to be the default. You can also have the X & Y axis bound together, or customize them separately. DPI goes all the way up to 10,000. They also have sections for adjusting Lift Height (Low, Middle, High), Angle Snapping (Enable, Disable), Pointer Speed (Slow to fast, and everywhere in-between), and Enhance Pointer Precision (Yes, No). I don't know what most of those do, but I assume it's good that they give you options.I don't know too much about the sensor itself, but I can tell you that the mouse is very responsive and I have seen no stutter or freezing whatsoever.-ButtonsThis is where I think the biggest downfall is. Most of the buttons are great, but Button 6 (next to writing, left click) is hard to press, and Button 8 (behind scroll wheel) can be hard to get to depending on your grip style. B8 I can forgive, because we knew that was there from the pictures, but B6 is unnecessarily hard to press. B7 (below it) has a nice, solid click when pressed, but not B6. I think this may be by design to prevent accidental button pressing, but I don't think that would've happened that much anyway. B6 is way too resistive compared to the rest.-Scroll Wheel The scroll wheel is really nice. It's segmented, meaning it has notches that make rolling it solid and tactile, but not difficult. It also has a nice rubber feel, but is not hard to the point of discomfort. It has a nice solid click, and feels very responsive to my finger. Do note though that it does not tilt. Only rolling and regular middle clicking. Since the scroll wheel was the first to break on my last mouse, I'm trying to be extra careful with this one, but I will update if anything happens with it.-Corsair Utility Engine and Customization as a wholeThere is a ton you can do. If this isn't your first time with Corsair, then you probably know what to expect, but if not, they really allow you to make the mouse your own. Between the color, lighting, and button assignments, there are a lot of ways you can customize this mouse. You can assign any of the buttons however you want, including having macros, keystrokes, shortcuts, timers, even media controls. You can have different modes and profiles for the mouse, of which you can change by assigning a button to do so OR by binding them to individual programs. Apparently you can even download custom profiles and lighting schemes from Corsair's website and upload your own. There's on-screen-display settings which I assume let you track your mouse's performance. There's even something called Cue Link which I believe lets you synchronize the lighting across multiple Corsair devices (like headsets, keyboards, and mice). I have not used it extensively, but I feel as though there's a lot to offer here for people who want/need a lot of customization. I really like what they have to offer, but definitely Google it more to see if there's a more in-depth discussion going on somewhere. Maybe ask around on Reddit as well.Quick Note: CUE has it's own forum that you can check out here:[...]-Other (Cable, packaging, Warranty, etc)The cable is braided and of nice quality. I think it will hold up very well in the long run. You may want a twist tie or a Velcro tie of some sort, because it is fairly long.The packaging was really nice, and pulls open so that you can see the mouse inside (like a presentation sort of deal). To get the mouse cable out, Pop Outwards the tab on the backside, not in. It took me a while to get that.The warranty is one year, I believe, but does not cover accidents or mistreatment. It's probably a good idea to pick up an Accidental Warranty from SquareTrade or another place.-Final ThoughtsThis is a really nice mouse, especially for the price. It feels solid and comfortable to the touch, the RGB lighting is really cool, customization is great, and overall it's very responsive and nice to look at. So far, I'm really happy with my purchase, but I will update accordingly if the need arises (which I hope never happens).