It depends on your career goal. If you want to have an advanced endoscopy exposure or want to go for private practice later on, Mayo Florida might give you a lot less number. The upside is you will get a lot of perks for attending conferences. If you are an IMG, it's going to be very challenging for them to retain you there and you will be having a hard time competing with other candidates (with experience in advanced endoscope) for a job in private practice.
Location wise, I will not rank Baystate highly. The hospital is in MA, but majority residents/fellows live in CT. That tells you something about the city.
Not sure about Pittsburg, but TX, in general, has a lot more demands for GI than many states + high-income potential without state income tax. It's much easier to find a job there if you finish the fellowship in TX. From your list, if other factors are about the same, I would go for TX.
My top 5 are:
- Baylor College Houston
- University of Pittsburg Medical Center
- Baylor University Dallas
- Uni of Utah
- Henry Ford Hospital