Pros
-Health insurance is phenomenal - low monthly cost and co-pays. -Access to the cutting edge techniques and equipment - if you have the grant money! -Great stimulating academic environment to be in for research, although can be truly cut-throat so be careful! - Researching at MGH does open doors for high quality collaborations within Boston and else where.
Cons
-Career progression and opportunities are targeted only at MD's and not PhD's. This is a real problem when trying to pursue a research career here. -Salary sucks and they know it - "it's a privilege to be at MGH" -Although there are extremely generous benefits such as long paid parental leave there is a culture of PI's pressuring postdocs to the point of threatening their job to not to take parental leave or holiday, therefore the perks are there but you may not be able to take them for fear of negative consequences to your career. - the standard research culture is to work 24/7 in order to get ahead in your career, this is probably a symptom of academia in general but it should never be like this.