My wife had the bypass 2 years ago and I was banded 2 weeks ago. Each procedure requires certain responsibilties for how you will live your life going forward.
My wife is very structured and takes her supplements without fail EVERY DAY. She has been successful with the procedure losing 115 pounds. With the bypass surgery, generally, it's get the surgery and move on knowing that there are certain dietary restrictions, sugars carbs etc "dumping"
The bypass for me is too rigid a lifestyle from watching my wife's experience. Having the band, there are maintenance issues - fills etc. but dietary intake is a bit more liberal with the exception of carbonated beverages and I like the option of it being reversable should I ever need to remove it.
You need to ask yourself honestly, are you prepared to take supplements everyday more than once a day and be restricted by certain foods for the rest of your life for the bypass or get banded and have periodic fills etc.