Barret's is almost always going to get pre-existing, non-covered status under individual policies. That makes such coverage unacceptable because you virtually must undergo periodic endoscopies and possibly eventual surgery (hopefully preventive).
My advice is to continue unrestricted insurance in any way you can even if it means deferring FIRE. This is not a condition you want to exclude. I am hopeful that health care reform will eliminate pre-existing illness carve-outs, which are inherently unfair and immoral for legitimate conditions (fine with me to exclude cosmetic or similar treatments)
On the bright side, there are some promising procedures under development which can provide treatment without esophagectomy should things start to look funny. They will be available in major centers within a year, I understand.
But insurance-wise, IMHO this needs to be covered whatever it takes.