Since the band is a restriction to the stomach, that is one of the drawbacks mentioned -- chew thoroughly or things may get stuck. Plus, it is a foreign object inside your body, meaning your body will try to fight it.

So far as the sleeve, I think I would (subconsciously?) defeat is by snacking all the time. Maybe you would lose you appetite eventually? When I cut back on calories I lose energy, get cold in the winter, have trouble focusing mentally. If I could only eat half a cup of food at a time, I'd run out of steam in a hurry. And to think that I could never go back...well, that would be very depressing.

OTOH, maybe your metabolism would change, you would adapt to the new normal, the weight would fall off, and life would be good. My BMI is in the mid-30s, which is high enough, but if it were in the 40s with co-morbidities, you are looking at problems even if you do nothing.