Big 4 experience is very valuable if you wish to pursue a career that utilizes accounting but isn't just an accounting job. Perhaps I can clarify this. If your goal is to be an auditor or tax accountant, then either the Big 4 or other “smaller” firms will be great for you. You will most likely have more free time with a smaller firm, but you'll probably be exposed to a bit more in the Big 4 (larger companies, more complex transactions, etc.). So, if you want to be an accountant, it wouldn't hurt to stray from the Big 4.
Working in the Big 4 provides a massive networking channel. Not only do you have contacts throughout the firm throughout the world, you develop relationships with the many clients you work with. Many of my colleagues have been asked to work for their clients in business fields that require accounting knowledge (but not only as internal auditors, treasurers, or controllers). The Big 4 experience has opened many doors for them.
I am still in my first few years of Big 4 experience and, while the hours really suck sometimes, I view this time as an investment in my future. I might be working 2x as much as some of my friends from college that went to local or smaller firms, but I also have been exposed to more than 2x the accounting complexity. I see this as a fast track to building a real-world foundation in business.
Now, I'm not saying that the Big 4 is the only way to get such experience. However, it is all that I know for now (aside from some ultra-boring industry accounting). It has become much more difficult to secure a Big 4 job but it's still possible.
Just my two cents…
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