Worth doing an articleship at the big4?

So I've just completed my IPCC Group 1 in November 2011 and got the results in February.

Now, well, the big question pops up.

Is it really worth doing an internship at the Big 4?

From what I understand, the exposure at the Big4 would be immense. The workload would be huge, and any student would only come out as a better man. Nonetheless, I've got a few questions regarding the internship at the Big 4.

1. Does it in any way become a hurdle for the preparation of CA Final? Based on your experience, is it true that more often than not, students tend to postpone their final attempt or fail it in their first go because they don't have sufficient time to study for it?

2. Because each student is confined to a given department, does this mean that the student only gains experience in that particular department? While I understand the experience in the field the student works in would be immense, does this really offset the advantage a student has while working for a mediocre firm in which he gets to work throughout the spectrum?

3. How does this affect the future prospect of a student? How many students who intern at the Big 4 eventually get offered a job with the Big 4 by the end of their articleship and after becoming a CA?

4. Do you suggest that a student should intern at the Big 4 throughout the 3 years of his articleship, or is it sufficient to work there for a few months, or say 1 year?

5. Overall, how is a student improved? While I am well aware that anybody working at a Big 4 would eventually become more professional, have better communication skills etc., would he really have a greater amount of knoweldge academically?

And I've been confused about the structure of the Big 4s in India. After doing a little bit of research, I've come to an understanding that Big 4's don't exist by themselves in India. They exist in forms of parternship. For instance, there's no such thing as Ernst & Young in India. However, there are a handful of partners of Ernst & Young who are affiliated with it. So a student essentially works under a partner. So this would also mean that work differs from partner to partner, and there's always a preference for a more renowned partner. In such case, how do we know which partner of E&Y or Delloites or etc., is better?

I'd greatly appreciate your help. I understand the questions are rather long, and a few are jumbled but any sort of help would be greatly appreciated. I'm really confused right now, and prior to this message, I wasn't really concerned about my articleship. However after talking to a couple of guys today, I realized I was slacking off and should make a decision as soon as possible.

Thank you in advance. And I'd appreciate it if you could quote a few examples.