Vantaggi
As Country-CEO for a Rocket Internet local portfolio company, I have had the best entrepreneurial training and experience of my life. The pace is super-fast, with incredibly long hours and a big load of pressure (a good pressure): I had to hire 20+ people in <1 month, build operations from scratch, and take on incredible responsibilities in very little time. The amount of trust Rocket Internet gives you is really empowering. It's probably one of the best "safe" arenas where you can have a true entrepreneurial training with limited risk (you have a competitive salary). Colleagues and management are smart and driven. Culture is a "no bollocks" one, which I appreciated, but may be intimidating to others.
Svantaggi
The company can be brutal. If metrics don't live up to expectations, or fund raising (done centrally) does not go as expected, they are as quick at closing down operations as they are at spearheading them. Obviously, that's exactly what the start up risk is, but, given that your equity stake is nowhere near what you would have if you were a real founder, you end up sharing a lot of the downsides, but your upside is limited. Make sure you know what you sign up for, but overall I would do it again, if not for the incredible training received.