I don't have Barrets yet but have severe reflux and oesophagitis. I wanted the sleeve, but my surgeon refused. He said I would be back to him wanting revisional surgery to gastric bypass down the track and it's much safer to do it right the first time. Since he told me this I have done lots of research and come across a lot of people that have had sleeve then needed bypass.
I would rather just get it right the first time so do some research to put your mind at ease. I am sure sure your dr won't agree to the sleeve