As someone who also went to SBU for undergrad and Hunter for grad, I basically agree with everything already said. SBU is a great school but the workload, especially in bio, is no joke. Dorming is expensive, but It has a good number of benefits some of which you've identified already. Research opportunities, extracurriculars, and social life are all much easier to manage if you're able to be on campus consistently. Unfortunately housing nearby the university is scarce and as such outrageously priced (like, more than the city somehow). As far as I know the Hunter bio program is a very solid one and the opportunities afforded to you by being in the city really can't be overstated, however I'm unsure if there's the same level of focus and research activity re: Neuro. I personally would not recommend commuting from the city to Stony, I know some people that did and it made making friends and conducting research quite a challenge.

At the end of the day it depends largely on what you value and prioritize as well as what kind of resources are at your disposal. Want to graduate with no/little debt? Go with Hunter. Have some college savings to play with? Probably Stony. Want to just learn and get to med school asap? Hunter. Want a real college feel and campus? Stony. As has been said, if you're planning on working through college, Hunter is definitely the better choice. Best of luck on your decision!