Pros: - very responsive
- included 5 , 3.6g weight
- well design
- very confortable
- cusomizable buttons
- scroll has two setting
- Build quality

Cons: maybe the price but I don't care because I love it so much

Other Thoughts: I recommand it ! if you research a very good and comfortable mouse, don't hesitated.The best gaming mouse a try. so much comfortable can pass hour and hour with it in the hand.before I have a mouse in the Cm storm Devastator combo and when I play with the G502 I fall in is charm .I'm a FPS player and I love it so much, very precise

Pros: To start, I actually bought this at my local Wal-Mart, not on newegg.

This mouse is amazing! Not only is it super comfortable to grip (no more sore wrists!), but the 5 included 3.6g weights are great in case you have shaky or otherwise strong wrists. Being able to switch between profiles and DPI on the fly is so useful. Have a super fast DPI when playing an FPS, but you need to slow it down while sniping? Press the DPI Shift button (it's right beside your thumb) and your DPI will switch to whatever DPI you have the Shift option set to until you let it go. While I don't use the scroll wheel in "freewheel" mode, it's really fun to play with, lol. Also, be aware that the two programmable G-buttons above your thumb may be used as the "Back" and "Forward" button when browsing the web. I also want to point out that when setting the weights in the underside of the mouse, be sure to really push them into their slots. They sit along rubber walls and if you don't seat them right, the cover plate, which uses a magnetic seal, wont close properly.

This mouse is absolutely butter-smooth. My old one was a standard USB desktop mouse (two buttons, one wheel), and it was janky as all hell. Aiming in CoD or lining up objects with precision accuracy in Garry's Mod was a pain until I bought the Core.

Cons: I haven't found any cons so far with the mouse's performance and ergonomics. My only complaint, which will not degrade the rating I've given, is that the weights or the rubber walls need to be slightly thinner as to seat more easily.

Other Thoughts: I've been recommended this mouse by a metric ton of people. My friends, LinusTechTips, experienced PC gamers, etc. I'd be insane not to tell others about it.

Pros: I have tried a lot of gaming mice and this is my favorite. Very responsive, wired so you never have to worry about connection problems or batteries and you can modify the weight depending on what you like. I've been using it as my main gaming mouse for over a year now and I still love it.

Cons: None.

Other Thoughts: I would recommend this item in fact I have purchased this item more than once as gifts to friends

Pros: Well designed for hand comfort, had this for 2 years now and still enjoy it.
Programmable keys on it ++ DPI speed choices to move the arrow over 2 screens with little movement.

Cons: None. can't go back to any other mouse.
If this ever dies i'll buy the same one over and over again.

Other Thoughts: Can't change much on this.
Buy one you'll like it and make sure you install the logitech gaming software if not already.

Pros: Customizable
Weight too
Like the shape

Cons: After a year and 3 months, the left button is already double-clicking.
I also have a logitech m570 for work and it had to be replaced and the new one too soon cause of clicking problems
Feels like the switches logitech uses aren't lasting long enough.

Pros: The software is good. Plenty of customizable buttons, click has a nice feel. Scroll has two settings, smooth, and a resistance wheel.

Cons: This mouse is way too narrow and uncomfortable. If you have large hands, chances are you won't like this mouse unless you like to claw grip it. Its also very clunky. When I make quick movements I can feel something inside clicking and vibrating, it feels cheap and annoying.

Other Thoughts: I switched from a much cheaper SteelSeries Rival, and I like the feel of the rival much better.

Pros: Good software and plenty of options

Cons: This mouse is pretty expensive but it's only been a couple of months from having this mouse and already it had started double clicking on me. Bad experience and I'm definitely going back to a cheap china gaming mouse that was as smooth as this mouse and lasted way much longer.

Other Thoughts: Would not recommend this mouse since you can get any other Chinese gaming mouse for so much cheaper with the same smoothness.

Pros: Fast, well designed.

Cons: None that I can think of.

Other Thoughts: It came on time, in good condition, and all the features work as described. Just a good gaming mouse.

Pros: I love the design of this mouse. The customizable colors / effects and the ability to add weights to the mouse to customize the feel are all great features. The mouse feels very sturdy and the buttons are very responsive. 3 profiles can be saved to the mouse for different colors and customizations (which can be swapped on the fly with a push of a button on the mouse).

The mouse comes with a long braided cable that can easily reach your machine. The cord also has a velcro strap which can be used to bundle up any extra cable so you don't have it piled up on the floor.

Overall a great mouse and am super happy I bought it.

Cons: Nothing that I can think of.

Other Thoughts: Buy this mouse

Pros: Build quality and looks

Cons: Shape for me didn't work I'm a claw grip coming from G9x. The body feels too long and too tall.
While gaming any lift off the mouse pad even less than 1cm loses signal. This is my fault but the G9x didn't do that to me. I guess its user preference and some might like that or not experience it if you keep your mouse hard against the pad at all times.

Other Thoughts: Please just bring back the G9x. Look at the prices on feebay, obviously it is a well regarded mouse that worked for many of us. I feel left out in the cold after having tried now 3 Logitech mice and nothing fits. If and when my G9x gives out I am not sure what I'll do. Alienware's Tactix or whatever is called I don't know maybe M65? Spend more time and a bunch of cash experimenting that's for sure. Too bad for me but I'm not alone I know this at least. Just bring back the G9x.