I feel ph.d has less positions than MS and you will work ~3 years later, while ph.d may make more than MS.

Does that MS program have a chance to transfer into Ph.D. program later on? If so, it seems a better choice. You could get a master first and then try to find a job or feel about ph.d. With a master in hand, you could also quit ph.d. for a job anytime you don't want to continue it.