Cons: This might take a lot of getting used to. The thumb buttons are hard to distinguish and having the ring finger button makes it hard to grasp firmly. When I push a thumb button, I almost always push the 3rd button. You can just shut that button off I suppose, but the fast action of an FPS makes this a little too hard to use. I actually prefer a weighted mouse, but the lightweight may be appreciated by some people.
Summary: I bought this to see if I liked it better than a standard mouse and the answer is yes. However, I had to purchase a different gaming mouse due to the size of my ginormous hands. The buttons on this mouse were too close together for me to use very well and I kept clicking two or more buttons any time I only wanted to click one. Also, the third mouse key, where my ring finger would rest was hard to get used to.
Cons: The sensor in the mouse is apparently faulty. The mouse will randomly skip around if you enable onboard memory and acceleration. Logitechs response to this is RMA the mouse for a replacement, as the G600 doesn't come with firmware updating, and the issue effects G600s with firmware dated before October 2012.
Summary: This is a nice mouse overall, but I have some minor issues with it--one, since it's so big (thick, in particular) it's not always completely comfortable to rest my hand on it for long periods--it makes my tendons ache somewhat, but it's not bad. Second, the thumb buttons aren't really all that useful.
Summary: Had this for a couple of days, using it with my MMO of choice, in large-scale group play. The item itself is working reasonably well. The driver/configuration software does intermittently glitch out in use, in a variety of ways: the configuration application detects that a device is there, but does not initialize so that the user can configure it; or, the device/driver suddenly/spontaneously forgets what keystrokes are assigned to which buttons (the buttons effectively...
Summary: It works as advertised. My hands are decently big but I've been a claw grip person for many many years now. I had adapted to a G13 so figured I'd give the MMO600 a go. As it turns out there are many design issues that keep me, personally, from rating this beyond 3 stars. Pros: Logitech - Honestly why buy from another mouse maker?
Summary: I've had this for about a year now, the same week it came out. After the time I've used it, I can say it's a bit on the heavy side. Also seems to be laggy compared to my G500. Not as great for FPS games. MMO, sure, excellent with all the buttons. Macros in games are fun to have too. Problems I have are when I go to go back a page, it goes back two pages. Double clicks the left clicker occasionally. Overall, great mouse.
Summary: This is a very functional mouse for gaming but the feel is wrong. The surface is smooth and feels slippery a different finish on this mouse would make it much better. Over all the mouse works fine, was easy to install and has no other issues.
Summary: This mouse is said to be an MMO mouse. People who play MMOs need to be able to press each of these buttons hundreds of thousands of times and they need to work every time. I have not had the mouse for more than a week and the G9 key is already having issues. I am a PvP'er, I participate in high intensity matches.