My mother had it done in 1992 - full-on gastric bypass, where they took out parts of her stomach and intestines. Her doctor had told her that she would die by the age of 40 if she didn't lose the weight. She never had problems losing, it was the 'keeping off' part that never stuck.
So, she followed the instructions and used the surgery as a TOOL (not a miracle cure) and became one of the 'poster girls' for the surgery. She went from 300 to 115 pounds (on a 5', very petite frame) and has kept it all off since.
The drawback with the seriousness of her surgery is that she can't absorb nutrients like she should, so now she has osteoporosis, mild anemia, and various other problems as she moves into old age. She doesn't regret it, although she wished they had the LAP band when she got her stuff done.
I'm keeping the LAP band as a last resort for myself. Currently I am in OA (Overeaters Anonymous) and working on the psychological issues of my weight for my health, as I am certain I'll end up with diabetes. Again, I'll do surgery as a last resort tool. I have no delusions about it being a miracle cure.