Anyone had Dr. Francis Teng?

After my first post : "Now what do I do?" I started checking out other Bariatric Surgeons.  I found two One is Dr. Francis Teng and the other is Dr. Thomas Umbach. Has anyone been patients of these doctors? What has your experience been? Are you satisfied with the results. Who would you recommend?  Is anyone going to Dr. Teng's seminar this Saturday April 9 at 10:00? I have so many questions.  Any there a website where you can do a background check on doctors?
 
Terri