Considering a lot of tests and comparisons on YouTube, the rear cameras are excellent. Auto-Modus tends to underexpose a bit in low light conditions, which is probably a problem of the software, because in manual mode you will be hard pressed to find a better camera on a smartphone.
Wideangle shots are much better on the V30 because it doesn't distort the edges as much as the G6 does.
The front camera is rather bad btw. No showstopper for me personally though, as I have made about 4 selfies in my nearly 20 years of smartphone usage
but if you are a vlogger, you might reconsider.