I personally wouldn't do it, but that my personal opinion. Time is one of the most important assets you'll have in your career and a Phd in FE is not worth the time, you can get the MFE instead and get the same job and essentially the same pay, with less time.
As a side note, I have heard bad things about the Stevens Phd program, Phd programs are usually free since you are providing your knowledge to the university, but I heard at Stevens, the fellowships/funding is non-existent, in other words not worth it. On the flip side, if you do a masters with them, I heard they provide some funding. If you're looking at Stevens, I would also look at IIT too, I hear they provide generous funding packages, but they don't have a Phd program if I recall correctly.