My mother had it done many years ago. Yes, she’s lost a lot of weight, but boy does she suffer when it comes to eating. She mostly eats soup now, because it goes down easiest. Many foods just don’t go down and she ends up throwing it up (don’t know if you can call it throwing up, because it never actually makes it down to her stomach; it’s more like coughing it up). My mother craves certain foods, like steak, but can’t eat it, so she ends up chewing it up and spitting it out. It’s quite… unsavory, to say the least.
A very close cousin of mine got it done as well, a couple of years after my mother. She’s lost very little weight because she’s sort of found ways to beat the lap band. For example, you’re supposed to wait 45 minutes after a meal before you can drink any liquid, but she gulps down water and tea while eating, which ends up pushing the food down more easily and giving her more room to eat.
People come to rely on the lap band and stop watching what they eat or bothering with exercise. I think it could be useful for the very obese, but I think most people need to suck it up and do it the old-fashioned way: counting calories and exercising.