I went through this same debate myself, as I currently work in tax, and I was trying to decide if it was better to get a MS in Taxation or an MBA with my focus being on tax and accounting. I think this is a very subjective topic, as every persons experience and expected results will be very different.
So with that disclaimer, I feel the MBA is slightly better if you ever have plans to move in to upper management, or if you aren't quite sure yet what field you want to be in long term. I wouldn't suggest paying big bucks for a MBA unless it is truly top tier, and I wouldn't go for one straight out of undergrad.
The MS in Accounting or Macc are good if you are just looking to pick up the required credit hours straight out of undergrad, and you are still undecided which direction in accounting you want to go. In general in industry the MBA is much more highly respected than a MS Accounting or Macc, I can't speak to how it is perceived in public.
The MS in Tax is going to be preferable if you are certain you want to stay in tax over the long run of your career. Again it won't be as highly respected if you eventually want to move in to upper management, but unlike the MS in Accounting or Macc it is much more highly respected than an MBA if you work specifically in tax.
Again these are just my observations having worked in both tax and accounting in corporate environments, so take it for what its worth.
AUD - 2/2013 - Passed!
BEC - 5/2013 - Passed!
FAR - 8/2013 - Passed!
REG - 11/2013 - Passed!
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