Pros
No stablished working hours, each worker decides how to manage their time; there are exceptions when you have to attend to the meetings, classes or other events such as workshops, congress...
Travel around the world when your scientific article is accepted by any seminar, workshop, congress,
being in touch with the last technology advances in a specific field.
Christmas, summer holidays.
Cons
Sometimes this research experience is not considered or counted as "Length of Employment" given that is not a private-company-job.
This job depends on the national fund, and nowadays is quite difficult to obtain money from the national agencies.