I had bought a samsung with my current PC and the tray malfunctioned in like 2 weeks. It used to open and close immediately when I pressed eject. I got it replaced and had the same problem in another 2 weeks. Now I'm using a LG GH22. 3 months, no problems yet.
looks like you got lucky. My friend had a problem with a Samsung NOT reading discs!!same here...though mine malfunctioned after 6 months...but my samsung sh-223b can read most scratched disks while my friend's sony & lg drives cannot...