You can do a lot of things with it.
You can run your
CFW of choice on your sysNAND and no longer need an emuNAND
Your sysNAND is now treated the same as an emuNAND, so if you fuck up your sysNAND, you can restore it so long as you didn't fuck up your A9LH install
You can boot payloads such as decrypt9, emuNAND9, Godmod9, Hourglass9, ect all before the sysNAND even boots
100% perfect boot rate into your CFW, for both emuNAND and sysNAND