Vantaggi
* The internship lasts 3 months and does teach you the general work environment very well.
* You receive constant feedback (as you request it, but it is available) from mentors.
* As a networking opportunity, you may form connections with various employees and especially your mentors.
Svantaggi
* The internship, despite what the course preceding it will often imply, is very unlikely to land you a job at the company.
* In the current market, these few months of internship don't make much of a difference on your resume. It still has its merits, but you must understand what you're getting into.
* Regular employees, who are used to seeing interns come and go, will more or less ignore your presence.