My two cents and my standard reply is that rooting is (almost) always the answer. Check out the rooted subforum for Virgin if you want to get an additional perspective on things. Personally, I root my devices on day one and then truly make them my own, and the SGS3 has by far been more awesome than any device I have ever owned in this regard. Good luck!
P.S. My other two cents is to not touch anything related to Knox with a ten foot pole. If you don't know what I am talking about, then definitely come check out the rooted forum for VM before you do anything else. Also some good discussion going on at XDA with regards to Knox and the most recent update, but on any given forum you have to sift through a lot of misinformation and half-truths before you find the good stuff that was posted by people who aren't just repeating rumors.