Hey everyone using ROG 6, they just rolled out an update today for the bootloop. I updated, put my sim back in, restarted the phone, and it's working fine now.To update go to Settings > System > System update > and then hit install
My method is turn off wifi, put phone into airplane mode, put sim into the phone, wait till the mobile data button goes from 'no sim' to 'data turned off' (forget exactly what it says), then turn airplane mode off and hover my finger over the mobile ...