I just rooted my phone last night. Before flashing my first custom rom I did a nand backup and I have some questions as to what exactly this backs up? Im assuming that this created a backup of my factory rom, correct? So if at any point in time I wish to go back to the stock rom, I just need to restore the nand backup and I will be all set? Also when flashing from one custom rom the next, I don't have to do new nand backups because I still have my original rom backup that I can always go back to, right? I just need to wipe and load the new rom.