Now I know that SUNYs are cheap, but you get for what you pay for, i.e. admin., no perks/scholarships, all student loans. You know what I mean if you've attended a SUNY. Most of the people claim the same advantage re: Downstate, it's cheap. That doesn't sound too convincing.
If you had to choose btw MSSM and Downstate, that's an easy one. But if cost is your deciding factor, make sure you really end up paying a lot less at Downstate. If MSSM gives you a low EFC, then you may end up paying only a little more at MSSM than in Downstate, where you're probably in for all student loans. Also, MSSM has a Sinai school loan that you won't have to pay until after residency, unlike most med schools. Do some calculating and in the long run, you may actually pay the same amount.