I'm had my braces on for about 7 months now.
Mine cost RM3200, should be worn for 1 and half year..
Not so severe case, rabbit teeth and no tooth removed for me.

Pain?
Yes its painful, like Xromix said it, every visit (every month) to the dentist. but after a few months you'll get used the pain and you'll know how to deal it.

My dentist told me, the retainers is a MUST MUST MUST after the braces are removed. If not, the tooth will move back.

My teeth is yelloish too.. since young actually..
My dentist said, the yellowish teeth tends to be stronger tha the white ones..