The days were employeers even see the font you choice to use for your resume has been over for more than 10 years. Your resume will be submitted electronically, fed into some database system, possibly e-mailed, and then printed out by the person doing the interview (if they like paper copies). Each stage will cause a loss of formatting. By the time you are done you are lucky if all the characters are still the same as what you typed. As for justification, ALWAYS use justification on any paragraph more than 2 lines long. If you are getting huge distracting gaps, you are using really poor quality software. In the end the only time someone will actually see the formatted copy is when you are there in person handing it to them, or if they pull it off your website. So in those cases you have complete control to do the resume the way you think it looks best.
Keep Up with TechRepublic