Vantaggi
The generous and liberal benefits. Good health care (with many extras added to the plans). Generous time off that you even get to take (sometimes). Heavily subsidized T-pass. Free bus between campuses (great if you live in Boston, work in Cambridge or vice versa). Theoretical 35 hour work week for non-exempt employees. Some folks actually have it, others not even close. Some very smart folks to work with. Some really exciting projects and challenges. The name means a lot on your CV or resume.
Svantaggi
The benefits have a cost and that cost is salary. Harvard is generally just not that competitive (to similar positions in the area). They are trying to make up some ground through bonuses / reviews, but the disparity remains very, very large at times. If you need to drive to either campus (Cambridge or Boston), parking is expensive and there is usually a waiting list for a permit. Don't expect a spot as soon as you sign on, unless you're a big wig. They don't seem to have the same trouble the rest of us do ...