I'll start off by saying that I own a Corsair keyboard, mousepad, headphones, and RAM and they're all great. However, I'm on my second M65 mouse in little over a year.
I purchased my first M65 from Best Buy and after a few months it started randomly double click (known issue as the forum search shows posts back from 2015). I contacted Best Buy and they said I had to go through Corsair to get a replacement. I contacted Corsair "customer support" and had to track down a physical copy of my receipt (which meant going back to Best Buy), then I was told I was going to have to pay out of pocket to ship the defective product to them. So that would be $10-$15, plus another $10-$15 for a cheap replacement while I wait for them to either fix the mouse or send a replacement.
Being halfway to a purchasing a brand new mouse (maybe mostly there if they charged me to ship a new mouse back), I decided to just buy one off of Amazon back in March since I thought the issue was a fluke and I really enjoyed using the mouse when it was working.
Well, guess what....4 months later, my M65 randomly double clicks and it also randomly fails to register a single click. So guess what, I'm done and I recommend anyone who is thinking about buying one of these to spend your money elsewhere.