I'm a mech eng and I am a P.Eng. but I never bothered with the master's degree. No one I've ever dealt with gives a rat's arse how many letters you have after your name. My job requires the P.Eng. Outside of that, it's "what have you done for me lately". Practical real world experience trumps how many books you have read.
Job prospects stink for someone who is overqualified and thus demanding of a high wage. Engineering is not a high paid profession in North America, which is a pretty sad state of affairs, but it's how it is. It gets better after you have "paid your dues" for a few years by working as a relatively-low-paid mechanical designer and are eventually able to break free of working for someone else ... I'm doing okay and I have more consulting work than I can handle.
Engineers who worked their way up from the shop floor, and understand how things work and how they are made, are of greatest real world value. In my world you need to understand robots, and automation equipment, and tooling, and machining, and system controls, pneumatics, hydraulics, and such things. Don't need a master's degree for that ... but you do need to get dirty hands and get splashed with hydraulic oil or machining coolant now and again. Don't get me wrong, I wouldn't have it otherwise. I'm much happier dealing with real stuff while wearing jeans and hard hat and safety boots, than sitting behind a desk.
And now, back to desk work; I owe someone a quotation, and I've been procrastinating, because it's for a big job and it's split in three parts and I need to put numbers to all of them ...