Successfully rooted my Samsung Galaxy S3 R530X (Ntelos) with your method. I couldn't reply to your thread to let you know to add the device to your list, since I am new to the forum. The thread that told me how is:
[ROOT] Saferoot: Root for VRUEMJ7, MK2, and Android 4.3
blockhart329, Can you confirm it didn't trip any KNOX stuff? Also do you have 4.3 -- R530XWWUBMK4? OTAs seem over and Kies 2.6/3 say this model isn't supported. The R530 is a small market and X version is even much smaller. I'm trying to learn and will be trying to find a good forum/sub to post in.
Not familiar with Knox. I was successfully able to change the MDN and a few other things. Then I tried to get Viper32 to flash it for me to use on Pageplus and he tried and said the phone could not be written to. I restord it to factory and returned it for a refund. According to him, these phones are only able to be used on the original network and cannot be flashed to another. I thought I had a pristine S3 for $80. Too good to be true I guess.
I'm going to get one of the new BLU 10" phablets and try it out. I hear they are great devices. I found one at z-cellular for only $240.00. Can't wait to try it out.