These are all well known attorneys in the MA firearms community. If any of them were doing a bad job, I expect that everyone on NES would have heard about it by now.
There is no big difference if you are going to one for advice. The big difference occurs when you pick one to fight a battle.
Your choices:
1. Assert dual residency and apply for a MA resident LTC. This may not be possible based on a part time address, and the pitfalls of trying this and having a LE agency disagree with you can be unpleasant. I would not pursue this course without competent legal advice (which may very well consist of "don't do it").
2. Own a business in MA and apply to the town in which that business is situated. The dept can, but may not, issue a LTC to a non-resident based on business ownership. (uncommon but legal)
3. Apply for a temporary non-resident MA LTC. $100 per year; apply through the CHSB; in-person interview in Chelsea required each year. If you are clean, you can expect this to be approved, however, getting one issued without restrictions may or may not happen.
Be sure to learn about the MA AW ban, the ban on carry on school property, and the MA safe storage laws.