There is no need to backup aboot, all the partitions (except modemst1 and 2) can be retrieved from the KDZ of your variant (these partitions can be extracted from the KDZ file).
Do not mistake modemst1 (mmcblk0p11) and modemst2 (mmcblk0p12) with modem partition (mmcblk0p1), they are different.
The unbrick.img of your phone is a secure measure, "just in case..." you face the infamous qualcomm qdloader brick, by using your own recovery image, you won't need to reflash modemst partitions afterwards to regain your IMEI data due flashing the image from other phone.
After restoring everything to stock, you may face FC's on first boot, in this case, just start your phone in factory reset ( vol - and pwr button, wait lg logo appear, etc...) and do a reset.
Last edited by F. Gacrux; 16th October 2015 at 06:14 PM.