I just bought both a Logitech g502 proteus spectrum and a corsair m65 pro rgb, because I couldn't decide between the two. Currently trying them both out and will return the one I like less before the return period.
Honestly they are both great, but each has minor issues.
Looks wise, like their keyboards the Corsair mouse looks gorgeous. The led effects are beautiful, the materials are really nice and it just feels like it should cost more than it does. The g502 feels plasticy and cheap in comparison. Also the led effect is only on the G on the mouse, doesn't look nearly as cool.
Fit wise it's a win for the g502. That thumb rest is so comfy, and it just feels right in my hand (I have a fingertip / palm type grip). The m65 shape is a little wide, and it's harder to get a good grip on than the g502. It's not bad, just not as great as the g502.
One issue I have with the g502 is that the left and right click has a weird spring action to it sometimes. I looked it up and others have complained about it too. The plastic on the buttons tends to stick to the skin of my fingers, so that if I'm doing taps like I'm am fps, it will lift the button off a bit and make a spring like noise. It's very annoying and I'm surprised no one here mentioned it. The buttons on the Corsair feel high quality for sure.
As far as trackinf, they both use almost the same optical sensor and both are great. But the g502 seems to track a bit better, or basically perfectly. Hard to explain without experiencing it.
The m65 is really heavy. It comes with all the weights in, and it was bothering me as I lift my mouse a lot. The weights are annoying to remove to. Rhe g502 feels just right out of the box with no weights installed, and the method used to install them is much easier.
Overall, I'm still pretty torn.
Corsair m65 pro rgb :
Pros
- much higher build quality (feels expensive)
- looks way better, beautiful led lights and just nice looking overall
- much better buttons
- the scroll wheel feels like clouds
Cons:
-heavy and wide shape, not as comfy
- software is worse than logitech g
Logitech g502:
Pros
- perfect tracking
- excellent ergonomics, feels great to hold
- awesome free scroll wheel
-software is easy and intuitive
- good weight (without the weights in )
Cons:
- cheap, plastic feel
- doesn't look as nice, weak led effect and gamer look
- left and right click sticky liftoff and spring noise (annoying)
Still not sure which to keep, but ergonomics and fit are super important for a mouse, and the g502 wins there. The Corsair feels more expensive and higher quality, but not sure if that matters as much with a mouse.
Maybe this helps someone? I think most people would love the g502 as many others have recommended here.