Pros
1. Right place to work for a fresher. 2. If projects are in hand with the company, onsite opportunities will follow you. 3. Lot of knowledgeable people are there to help you though most of them are leaving now because of the treatment they got for their hard work and sincerity.
Cons
1. Manager and Senior Manager level employees are not upto the mark to help you or mentor you. 2. In onsite you are purely responsible and don't expect any help from the offshore team even to resolve a single small bug. The mistake is not yours that the client company not paid well to 3i Infotech, but the development team heads will think so and give less priority for your project. This will lead to client escalations and finally the person at onsite will be screwed.