Well, tomorrow I'll find out. I'm a 6-year Bandster who has had nothing but grief with the thing. PBing, vomiting, unable to eat solid proteins, esophageal stacking, reflux, dehydration leading to a monstrous kidney stone, you name it. I am having a revision to a sleeve tomorrow, and never considered the by-pass for more than a few seconds. My mother is a retired nursing instructor, and she said that no one should get the by-pass unless they weigh a 1,000 pounds. Osteoporosis is BAD in my family, and I can't even consider a malabsorptive procedure like the by-pass. The only thing my mom wants me to ask the surgeon about is B-12 shots, since the fundus of the stomach makes the intrinsic factor, which enables us to absorb B-12. That's all she's concerned about. For me, the sleeve is the only option. Good luck with your research. It's a very personal and individualized decision.