So here is the test with just a Zippo lighter, had actually burned my finger during the test and gotten a heart shape blister on my trigger finger. But was interesting actually only using a lighter as a light source and it works pretty well with the f1.2 and f1.4. The test I kept ISO800 as the max because anything above would cause extreme ISO noise into the picture. However would had been wonderful if Canon came with same high ISO noise cancellation like Nikon, but might happen next year in the new cameras. So here is the video showing you the results of the test.
The difference between the f1.2 and f1.4 is not that extreme different, but also want to say filming at night you really need to buy extra lens and not using the kitlens. I actually saw someone trying to film an event at night using a 18-200mm f3.5-6.7 and was pretty stupid and asking the organizers the whole time to put spotlights on, while the person who is filming for the event should actually be carrying own lights or use better lenses for low lights. Cause I filmed the same event with just the f1.8 lens on iso1600 but able to capture the event without the extra spotlight, plus I always got the backup external LED light I can attach to my hotshoe, if its just way to dark.