I currently have the Samsung Galaxy S4 - MF3; v4.2.2; i337. I got the phone unlocked (direct from AT&T); and then
1. followed this method to root my phone - http://forum.xda-developers.com/show....php?t=2387577- Worked.
2. Got Safestrap v3.65 - http://blog.hash-of-codes.com/downloads/safestrap/ - Worked.
3. Tried 3-4 different ROMs, none of them have worked.