Yes, they do, they are. It sucks. Logitech is the worst. I've bought some of their (not cheapest) mice and they all started double-clicking in 6-12 months!!! An

Yes, they do, they are. It sucks. Logitech is the worst. I've bought some of their (not cheapest) mice and they all started double-clicking in 6-12 months!!! And when I tried to resolder switches on my G100 the tracks started to peel off the PCB - and I'm an experienced engineer. I ended up switching switches with a cheap A4Tech lying in a closet. And these still work. Shame on Logitech. In the era of M-SBF96 they were making reliable products.