I can't figure out if I'm a light sleeper or not. Sometimes, I sleep right through my alarm clock, yet sometimes, the sound of a vacuum cleaner running in my neighbour's apartment can wake me up in a flash. It's quite annoying.
Also, placing my alarm clock right next to my bed does me absolutely no favours for myself and for my neighbours (or my future university roommate). I almost always subconsciously smack that snooze button, and by the time I'm awake and alert, I find myself waking up at around 11am-noon (depending on when I go to sleep).