[elonmollusc]

I worked for a few years and then went back to a Ph.D. program.

It's now possible to do an M.S. while you're working. There are now a number of good online programs, with Georgia Tech's OMSCS at the top of the pile. You might want to take a year or so in your current position and then evaluate whether an M.S. would be a career enhancer. The culture of Master's programs nationally is shifting towards working professionals doing their degrees online, so the case for quitting your job to go back to a full-time residential program is going to get weaker and weaker in the coming years.

Ph.D. is a totally different game and a bigger conversation. Short answer: unless you really, really want to work in academia it's not going to be worth the opportunity cost.