Logitech replaced my G15 (original model) keyboard because it suffered from excessive light bleed through the keycaps. They announced that this was a design flaw, invited people to send their keyboards back and sent out brand new ones instead.
In the end they didn't get around to collecting the old one. I still have it. I also still have the replacement - I'm guessing that keyboard will outlive me.
Admittedly that's because I'm using a different one as my main keyboard now - Corsair K95, with mechanical goodness. It's not bad.