What are your opinions on these songs?

http://www.youtube.com/watch?v=aiXK8rh6Fg4

http://www.youtube.com/watch?v=UkZt7tZl2AE

http://www.youtube.com/watch?v=z4nKOzk8qbw

And last, one of my favoirte songs:
http://www.youtube.com/watch?v=3Lr_RSkIlE4feature=related

Tell me what you think of each one. And please take the time to
listen to each full song. Thanks!