Thats great that you reached your mark, but you really aint proving anyone wrong. The doctors have to give conservative numbers because of the amount of failure, as well as not wanting people to feel unsuccessful. But wither way, make your goal and exceed it, that would be an accomplishment.
My doc told me that i could ideally get to 200 pounds. that is still horrible to me. I have set my own goal, and I hope to meet that goal and keep it. I want to lose a lot more than that.
But congrats and good luck on the journey.