I've lost 100 lbs with my lapband over the last four years so I've heard a lot.
Frankly few have been snarky and those have left me be after telling them that I'm happy with my choice. So while it is good to be prepared try not to go in crazy paranoid and on alert:)
The vast majority have been supportive and interested and know someone who is contemplating. I think I've talked to at least 100 of those people when I've given my card and said "have them call or email if they want to talk about it."