Pros
The best thing about working at Simulia is that in general you get to work with very smart people. Working environment is decent but the neighborhood is not that great. Vacation is decent.
Cons
The company had a very a good reputation (and to some degree it still has) in academia and it was able to attract young and talented developers from top universities (UC@Berkeley, Brown, Duke, Northwestern etc.). Since ABAQUS became Simulia things have changed and not necessary for good. Company has expanded with several extra-layers of management and with non-technical people who give you the feeling their job is just to find new ways to make you less and less efficient. Salaries of the technical people are mediocre for how expensive New England is. Benefits have been cut: employer contribution to 401k has been reduced, employees now have to pay for their health insurance and you have to work more years until getting more vacation days. It is very difficult to get promoted even if you are dedicated 150% to your work. Promotions are not transparent. Even if you are promoted your salary raise is not much above the inflation. Consequently, talented people left and it seems it’s more and more difficult to attract new technical people. There’s no training for developers. You have to learn everything on your own or by going to the right person and asking the right question (and hoping that person is going to actually answer it.)