Applying for biomedical PhD with partial M.S. credit?

[ss2player]

Greetings all,

I'm weighing some options about my future and would appreciate the vast insight of the forum. I'm currently a research tech at a small private university on the East Coast, and have started taking Master's classes part time with my tuition benefit. However, I have been interviewing for employment at a nearby Ivy League university that would pay approximately 40% more. I would eventually like to go into a PhD program in the biomedical field, but need some input on timing. 

I have completed 8 credits at my current university for a 4.0 GPA. If I take the new job, I would like to use their benefit to take classes there. Only catch is I have to be accepted into the program; I had a ~3.0 GPA in undergrad and 600V/720Q/4.5 GRE score in 2010. I'm wondering if I should focus on trying to get into a PhD this round with my 8 MS credits (likely 16 credits after classes in the fall) and turn down the job, or accept the new job and try to get into their better MS program and then try for PhD next year or later.

Would more credits make enough of a difference in PhD admissions to turn down the pay increase and Ivy research experience? Or would I be better off with the extra cash/experience and take the risk of not getting into the Ivy MS program and be stuck with 8 credits for future applications?

Any thoughts would be well appreciated, this is proving to be a difficult choice for me.