A good news story.
Back in the dim dark days I bought a Logitech MX518 from a well known etailer. This month it started disconnecting and reconnecting to a chorus of USB beep-boops. I rang the etailer who told me that they only covered the warranty for the first 12 months, after that I should call the manufacturer.
Fair enough, I thought, and a quick Google later I was on the phone to Logitech's customer service. We went though a few quick diagnostics over the phone, new drivers etc. The operator informed me that it did indeed appear to be faulty and that a new one would be couriered to me forthwith. I have received various tracking emails from UPS, and can see that my new mouse is currently in Barking on it's way to me.
Thanks Logitech, quality work. I'll be buying more of your products just as soon as I get a job !