TC Pros:
Music room
If multiple choice then you got your grade immediately
Can take when it works with your schedule-sometimes class would be cancelled and you could take during class hour

Cons:
Sometimes the music room is closed
Tests could be really long, although it seemed to me that it got more popular to put time limits on tests
Long lines possible

Also I was dating a girl briefly and she went to take a test. Some dude left his number on her desk as he walked out. Apparently this made her decide she liked single life more than being my girlfriend, so that was lame.