Question about Ph.D. Accounting - Admissions

I'm still a few years away from applying to a Ph.D. program in accounting (I will be finishing my M.S. in accounting this December), but I would like to get a good idea about where I will stand 3-4 years from now when I begin applying.

My question is: How valuable is your work experience in the admissions process?

I'm asking this because after watching several videos from Ph.D. accounting students on the adsphd website and noting that all of them have a few years of Big 4 experience, I'm feeling a bit discouraged. I'm currently working in a small tax practice with a staff of less 10, two of whom are CPA's (I will soon be the third as I have the exam passed but do not currently meet the experience requirement.) Despite the size, we process about 1,500 returns, mostly individual, but we have a good mix of corporate/partnership returns as well.

I understand that there are a number of other factors involved in the admissions process, but will my work experience put me at a disadvantage compared to someone who has the same number of years of experience in a Big 4 tax department? If so, will a super impressive GMAT score compensate for that?

I'd appreciate any input on that.