look here for salary estimates and do the math for your case:
http://www.electricalengineersalary.net/
Only Bachelor of Science Degree – $55,328 – $73,550
Bachelor of Science in Electrical Engineering and Master of Science – $60,350 – $86,607
from the lowend rates abve it looks like starting a job as BS EE over 5 years you'd get
maybe a 10% increase in salary which would mean you'd be getting what a starting MSEE gets after having worked 5 years.
However in that 5 yr period the starting salary for an MSEE would probably grow to $70K and so you'd still be behind. My guess then is going for the MSEE now is the better option (besides you get to party longer) also your study skills are still as sharp as they ever will be making no more difficult.
The caveat is my guess on the $70K if MSEE starting salaries don't change then going to work is better in the short but you might have regrets later on as higher degrees open more doors.