Vantaggi
Some managers are really good. but remaining all the things are bad.
Svantaggi
Dont know who is the manager and who is the sub ordinate. Managers work as a subordinates doing subordinate's work and some people acts as a manager (frankly speaking as the owner's of the company). And I observed that you have to beg for projects and do couple of projects at a time, if you are not in projects, you may be fired. Some people have regional feelings, and they used to talk in their native (indian) languages, even after several requested, they used to talk in their own languages. And whatever you discussed at the time of joining, just get the confirmation in writing (like working in a specific location & tranfers etc.), otherwise they will forget and force you to do the things which you are not committed to do.