Another positive experience with Logitech customer support here. Earlier this year my MX1000 mouse wheel click started to become unresponsive at times. Contacted customer services about it, who said they'd give me an entirely new MX3200 wireless keyboard and mouse because my MX1000 was part of the MX31000 set I had. I asked them if I could possibly go for the MX5500 set instead and pay them the difference. They said they were happy to give me the MX5500, I'd just have to wait a bit for it to arrive in stock! Got it a month or so later and have been very happy.