When flashing new ROMs it is recommended to wipe System, Data, Cache, and Dalvik.
You can manually format these in the mounts menu.
Or you can use the option to clean install a new ROM, which will wipe all necessary partitions.
Sent from my SPH-L720 using xda app-developers app
Devices: Samsung Epic 4G Touch, Asus TF700T, Sprint Samsung Galaxy S4, Galaxy Gear Watch
PM me of you're interested in Phantom Hackers last release of Gingerbread Blazer ROM for the E4GT.
TF700: ROM: Negalite WondeROM 4.3
ROM: CROMi-Xenogenesis 5.1 Kernel: KT-SGS4-JB4.3
Kernel: 3.1.10 _that OC+ Modem: MK2