http://en.wikipedia.org/wiki/Duodenal_switch here ya go Andy.
pros of the duodenal switch: better result in the long term, able to eat more so going to a restaurant won't be a pain in the ass
cons of the duodenal switch: have to eat more supplements for the rest of my life, more risks
pros of the gastric bypass: less supplements to take on a daily basis, surgery is less risky
cons of the gastric bypass: not the best long term solution, a very small stomach so going to a restaurant would be waste of time and money.