Default [Q] need some info

I am new to this world of rooting phones and flashing roms. I have a ls980zvc. I am rooted and i have backed up my phone with twrp. I know how to download wipe and flash roms i have this one question.

My question is if i flash one of these zva based roms such as optimus de, would i mess up my phone.And if it can mess up my phone, how can i go back to zva. Please try to break it down barney style. Thanks