I rooted and put CWM on the wife's GS4 but had to use SaftStrap with the CWM according to what I have read there is no TWRP for the MK2 build yet if that is what your on and only SafeStrap and limited customs are available . I have only rooted and supersu on her phone and not brave enough to do a custom yet . My understanding the OTA update installed a lot more security than what the MDL build was plus something called Knox. I prefer the HTC One phone, less security and much easier to get around in. Just my preference.