How about both?

I can't work full time and go to school full time. Going to school full time means I finish faster and accrue less debt.

I got ya

You could do both, but I say go for the MS. MS = better-paying job plus a SHIT ton of job offers. YOU WILL BE GETTING THESE JOB OFFERS AS YOU'RE EARNING YOUR MS. If you take those job offers, they will usually be contingent on you continuing or MS. If you take an internship, they'll probably be paid internships to give you job experience as you're getting it.

I think I will struggle with school full time, even more if I worked full time on top of that. I am considering internships that might even carry through the semesters.

Well, also keep in mind that "full time" is measured differently at the graduate level than it is at the undergraduate level. Full time in grad school is usually around 9 credits rather than 12 which is usually the undergraduate standard. But check with your university.

Yup, I am well aware of that.

If I start grad school in the fall, I can count 6 credits of classes I took for undergraduate. That would leave me with 24 credits, 21 coursework and 3 design/independent study. It is possible to complete in 1.5 years, but it may take me 2 or so years. My adviser, who has known me for 3 years and taught me in a few classes, thinks that I could pull it off on the shorter side. Hopefully he doesn't think too much of me. xÞ

Since you're in a scientific field, I would definitely say go for the Masters.

I'm much more on the engineering side than I am on the scientific side.