PROS: The Feel: The overall feel of the mouse is top notch. It feels well constructed and solid, no flimsy or cheap feeling areas. The texture also is top notch, providing a more grippy, rubber feel than the more slippery, direct-on-plastic feel of some others. The mouse also has a fairly wide foot print, so it feels very meaty and substantial under the hand. I would say its also a little more on the heavy side for a gaming mouse. If you are someone who prefers a really light mouse, this may be a con for you. Your hand just rests really easy over the grippy surface, and it is a great feel to me. The only potential downside is that the mouse makes the palm of my hand feel a little warmer than some other mice. This is due to the texture and the wide footprint of the mouse which brings more of your hand in contact with the mouse surface. You get a good solid contact grip which is great, but that decreases airflow around your palm.This isn't really a con for me however. This is also the only mouse that allows you to slide the thumb grid to fit your hand. Features: The mouse has all the typical bells and whistles. Lots of lights and ways to adjust them, if you are into all the flashy. The software is full featured, allowing me to do most everything I like to do.The mouse doesn't separate itself from the competition in any way with its software or feature set. In fact, I would rank it a tad behind that of Logitech, due to some small quirks. Those quirks are minimal, and Ive not had any real problem making macros, assigning keys, etc. The software seems reliable and loads quickly, and seems to keep a pretty low profile on the system resource front, which is great. CONS: The only cons I have so far are the software has a few little quirks. One example: Trying to bind a push-to-talk key for use in teamspeak. When I set it up, as I have with many other mice in the past, the key will not hold while I keep it pressed. It wants to register as just a quick keystroke, so it keys my mic for just a second then unkeys, even though Im holding the button. You can set the key to register a long key press but you have to specify a length of time, which simply wont work. I eventually just set teamspeak to toggle the key press so I have to tap the key, say what I want to say, then tap it again to unkey. In games, this problem doesnt seem to exist, as Im able to hold my "Ctrl" hot key I created and fire off abilities just fine, so I know its holding the key there. I hope to find a fix or workaround for this when I have more time to investigate. I just know that I have not had this issue on other mice with teamspeak. Aside form this issue, the software has tons of features and customization options, but isnt the most user friendly - there is a small learning curve with how it works. This is where I feel logitech has the edge, as their software feels better layed out and more "common sense" in how it operates. I hope corsair will keep working at the software front to match the quality of the mouse design itself. One other small con for me is the DPI light, which adjusts its color based on your DPI setting, is really bright and cant be turned down. This is the only light you cant turn off, and it is situated as such that it could be seen as distracting to some. Im really nit picking here to try and find potential cons. CONCLUSION: In conclusion, I think this mouse is perhaps one of, if not the best MMO mouse's out there right now. The physical design I feel is just superior to that of the Naga, which I also own. It feels well made and designed. The software could use a little more TLC but it is full featured and will do everything you want to do with a multi button mouse like this. It also doesnt skimp on all the flashy if you like that. If you dont, most of the lights can be turned off or toned down. The sliding thumb button grid is a new twist that no other mouse offers, and just adds to the great physical design corsair put into this mouse. Id rate it as a 4/5.