Their loss. If I didn't live in an RJ base I would still be on the brasilia. I had much better seniority so I was able to hold higher credit lines with more days off. At least the first two and possibly the first 3 years on the brasilia you'll make more than any RJ FO of the same longevity.
I haven't heard of us having many problems with the brasilia classes. There's a new hire class in the training center right now. I have heard that overall we're between 5 and 10 short of the number of people we would like for each class (brasilia and RJ combined).