I have a K70 RGB that I bought after I spilled soda on my K95 (non-RGB). The K95 actually still works, but I wasn't sure if it would work again. Anyway, my complaint with it actually has to do with the software. Without the software installed, the media keys actually work, but with the software installed, they don't work at all. I've also found it harder than it should be to setup simple color schemes. For example, I actually like the default scheme that you get without the software installed (WASD in white, rest in red), but the only similar variant that I can find is the same coloring scheme with a slow breathe effect. I could probably figure out how to do it myself, but it seems like way too much work.
Just to color the keys is mad easy. The timing and pulsing stuff is more difficult, though. I'll see if I can make a profile for the default tonight. I've got a k65 (tenless), though, so not sure if I can.
For the topic, I had a Ducky Shine 3. I used it for almost a year before replacing it with a Corsair K65.
The issues with the Ducky:
1. It shipped with two Esc keys. One in the normal spot, and one where the F1 should have been. I had to send proof to them to get them to ship an F1 cap to me.
2. The spacebar squeaks after less than a year of use.
3. The USB cable is detachable. It seemed like a solid USB cable at first glance. However, the place it connects is recessed, and you have to push it in at an angle, and also remove it at an angle, so you end up bending the connector.
4. The backlights on random keys completely stopped working. First it was just the B, then over the next few days it amounted to I believe 6 random keys not lighting up at all. They say you can replace the LED, but I've ruined 2 tools and torn the plastic LED housing up pretty good, and still yet to get a single LED to detach from the keyboard.
I was still in return period at the time this happened, so it was definitely less than a year. However, I couldn't find the original black WSAD keycaps that came with it, so I was out of luck.
The issues with the Corsair:
Really love it. Only (very minor) issue I have had was when I connected it to a new PC, and installed a newer version of the software than I had on my old PC. I think it did a firmware update. But when I moved it back to my old PC, it would not work until I reinstalled the software.