I don't use these 'levels' to define what my friends are to me but, I do have people in my life I consider to be my best friends. The way I see it is your either my friend or my enemy, plain and simple. I don't expect my friends to rely on me to be there for them through the good and the bad but, I always will be, I value all of my friends equally as no one in this world is more important than anyone else.
I love all of my friends and would take a bullet for them all if I had to.