Hello Salinasmaya,
I can only speak from my experience but when I did my psych. eval it was a one time deal (so far I don't know if there will be a follow up.) The eval was done in my Dr's office, in fact most of the consults were - exercise, nutrition, upper GI, and gallbladder sono. When I did it, I sat with the psychologist and she asked me a few questions and took some notes. It took about an hour. It was not bad at all but then again I don't know what anyone else's was like. I was banded on Wednesday and I have to say that this web site has helped me during every step. Hope this helps good luck with your journey.