New one (this is the replaced model) - works with zero problems. Old Mouse worked great but randomly on my old PC and now a brand new one Left click button stops registering until I unplug it from the PC and plug it back in. I e-mailed Support and less than 5 business days later, two e-mails, one with tracking info for this one and a 2nd e-mail with an apology!!! I will buy Rosewill again because I know that will support their product!! Pro: Very smooth, easy setup and fairly intuitive software. Could be one of the best gaming mice for the price. My only request is that they add support for motherboard RGB settings so they can be in sync (ASRock, ASUS, ETC...) Con:No cons other than the left click stops working randomly and unplugging it and plugging it back in to fix it. But warranty department replaced it with no trouble at all. A product isn't only as good as the company behind it and ROSEWILL stood behind it. Yes it had a small problem but they replaced it with no hassle. 4.5 eggs!

I purchased this mouse on sale for $30, so take that into consideration with my statements. Also, i do not have any experience with other mice, so i have no idea how this stacks up to others. What I can say though, is that i am incredibly satisfied with my purchase and i greatly enjoy this mouse. Pro: Feels solid in the hand, light but sturdy. Braided cable is a plus, feels pretty quality and not cheap. Two swappable panels, one for each side of the mouse. This means there is an optional ergonomic rest for the ring finger on the right side of the mouse, and a swappable panel for "FPS mode", which replaces the 9 MMO buttons with 3 more differentiable buttons on the thumb rest. These panels swap in and out easily, but they do not fall out during use, so these work very well. Very robust customization in the software. Different profiles can be created for different games/genres, and the mouse buttons can all be assigned to various different functions. There is also a great deal of customization for the DPI/sensitivity of the mouse, and a plethora of choices for the RGB lighting. Con:None that I can think of.