“I want to prove to myself that I can hang with the top dogs at the big4 firms.”
Lol, I think it's funny to call the Big 4 top dogs, but to each his own. This is enough of a reason on it's own. If working at a Big 4 is a personal goal, and you would regret not joining if you had the chance, then go for it.
“The prestige of working for arguably the top firm in the world is also a factor.”
Yes, this is a big part of why it's beneficial to people. Instant name recognition on your resume no matter where you are in the world (almost).
“I plan on staying until I'm at least a senior which would happen in about 3 years. After that reevaluate and see how I like it. If I like it, I'll keep going for manager and up, if not, maybe have an intercompany switch into a different department in the firm.”
I'm glad you are thinking logically about this. Setting short-term goals is the only way to really think about your career. Any more than 2-3 years out, you're just bullsh*tting with yourself. No one can predict that far. Always explore your options as you'll regret not taking chances with your career. I remember sitting in training and one of the leaders was a 2nd yr manager. Someone asked him what his LT goal was, and he said he didn't want to stay in audit, or even in accounting for that matter. His LT goal was eventually to move into finance/marketing. I remember thinking to myself “yeah, good luck, bro”. He spent far too much time in audit than was useful to him, and will end up having to take a huge pay cut to try something different… most likely. Once you spend 5+ years in audit, it's very difficult to switch into finance and continue to progress at the same pace as you were accustomed to.
“The fact that they promote intercompany change like that is a huge benefit imo.”
I disagree here. They advertise mobility, but it really isn't that easy. It's much more complicated than raising your hand and saying “hey, I'd like to do a project in advisory”, as audit (or tax) will hog all of your time, and you might get a chance if your schedule permits and you have a good relationship with someone in the practice you're trying to get into who wants you on their client. I'll put it this way, of the 5 people I know from my old firm who went into M&A from audit, 3 of them switched to another firm in order to do that. I'll let you interpret this however you please.
General points: I think Big 4 is a good place to start, especially if you don't have concrete long-term goals (i.e. “I want to start my own tax firm”). In general, it will offer you the widest array of options and your resume will more easily pass through someone's hands than having Joe Smith & Associates on your resume. The fact is, perception is just as strong as (if not strong than) reality. Additionally, outside the Big 4, it's very difficult to get public company experience (something like >90% of SEC issuers are audited by one of the Big 4, for reference).
Anyone can come up with anecdotal evidence suggesting a small(er) firm is better than Big 4, and they may be right in those situations. But, like I said, **all else equal**… Big 4 > small(er) firms.
Good luck!
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