Pros
1. Good exposure to many different areas of biomedical research. 2. Offer many opportunities to interact with fellows and PI (but one needs to be more outgoing, "step out of the comfort zone". 3. Still not too constrained by budget restrictions although money has become tighter and tigher.
Cons
1. Bureaucracy is slowly killing off the good joy of doing science. Nowadays, support personel (secretary, office manager, HR) has become your boss. More and more rules are put in place to restrict reagent purchase, travel, etc. 2. Strangely, one can feel very isolated in this place. A lot of internal bickering, elbowing can be seen in many groups. One needs to step out of his group, interact with other labs to fully benefit the opportunities, otherwise, you can be left in your own corner. Speak up, step out to get help, no one will come to you willingly to provide help.