I had previously posted on this forum about how my G40 had started recording lights in low light conditions oddly, including a large horizontal flare from lights that had not previously occurred the previous 4 years I owned the camcorder.
After failing to find the problem I upgraded to a G60. This however has the same issue except the flare is vertical. However the difference is that the flare has been there since I first got the camcorder. I can't see these flares in anyone else's footage using the same cameras so I am hoping if someone can confirm that this is normal for the G60? I wouldn't expect such poor quality from such an expensive camcorder. Below are some screenshots of the issue.
Based on the examples you provided these appear to be expected and the result of bright sources of light in the image combined with a "stopped down" aperture rather than a specific camera or lens defect, changing camera model or lens would not change the way the bright light sources are rendered.