I was hanging around the G4 forums on XDA before I bought my G4 and folks over there mentioned finding a 'stripe' down the side of the screen (a defect in the coating on the glass). It was easy to miss, but no way a brand new phone should have a blemish out of the box.
Went to get my G4 a day after availability in Canada and the store rep said I was lucky and that they had limited stock. She opened up my new G4 and I pulled the packing film off the screen and there was a half inch stripe on the upper right side of the screen lol. Said I wanted another one. She went back, got another G4, and that one had an inch stripe down the screen in the exact same place. She went back and got the last one she had in stock and that one was in good shape lol. She was pissed though. That phone had a screen sensitivity issue that was not corrected until a software update about 6 months later. Phone also later had the bootloop issue.
So I believe that forums like these should be considered before adopting early for an LG device to check for issues (or any device...my current Samsung S7 had the missed tap issue along the bottom right of the phone, fixed with a software update months later).
Will I get a V30 shortly after release? Probably lol. But I'll be checking forums a lot to see if there is something to keep an eye on.
But this is the only review I have seen that has indicated an issue. Most are glowing reviews, other than the odd software hiccup that is to be expected in prereleased devices.