You can gain the weight back – “eat around” – any surgery. The Lap Band is the biggest pain because you have to keep going back for adjustments. It’s a foreign body that can slip and/or cause infection.
The sleeve is the first part of the RNY procedure that also involves rerouting part of the intestines. Sometimes extremely obese people have the sleeve first because it’s too risky to have the whole RNY procedure done at once.
Google RNY for more info.