Pluspunten
The benefits of a direct work model (charging each of your hours in a 80hr pay period to specific projects) is you get the autonomy to say yes or no to whatever work comes your way. This allows you to try out a lot of different roles in different projects and mold your own unique path.
Minpunten
You can just get kicked off a project with no warning and no real reason except "it wasn't in the budget anymore" or "we didn't get as much money from the sponsor as we wanted," and because MITRE is not-for-profit, there's no overhead charge code for that missing project time. You either need to scramble to find a new project or use your PTO to fill that allocation. There's also no guarantees to have project work once you get a job here. You have to continue to network and find work basically the whole time.