I think the problem with my 360 might have been something to do with a short one second power outage we had while I was playing Geometry Wars a few weeks ago. But anyway what I got back was a refurbished unit that by it's birth date near the serial number on the back, was manufactured two months after mine. Now I know some people would be unhappy with a nice clean fully working refurbished model, but I am fine as long as it works.
After turning it on and putting Oblivion in and playing for a bit I noticed three things. Firstly upon turning the 360 on the drive tray sometimes forgets that it is closed and requires me to press the eject button twice for the tray to come out, I would be annoyed by this but for the second thing I noticed which is that the drive is quieter! Not silent, but as quiet as the standard PC DVD drive. And thirdly my Oblivion disk had a read error on injured sounds, so if my guy was attacked then there would be a delay as the drive struggled to read the bad area on the disk and sometimes it would popup a disk read error that required me to restart the game (I save often so not a problem, just an inconvenience). So really the whole tray sticking thing is a none issue as sending it back again could mean I get same drive that I had before which looking at Llamma.com's 360 DVD Drive Comparison I had a Hitachi and now have the Samsung which apparently isn't the quietest, yet I know it is way quieter than the Hitachi.