Can't say I get the chemistry or physics of how bulbs can make more or less light with the same power usage (maybe the alloys in the filaments), but don't forget their definition of say, "200% brighter" is probably legally allowed but is not necessarily meaningful. Light output may well increase with these bulbs, in certain parts of the visible spectrum, but I think it's logarithmic, like sound. And "twice as bright" say, doesn't mean the eye actually sees it as twice a bright - with sound, a 3dB increase is twice the power, but is only slightly louder. To get twice as loud, you'd need 10x the power. Not sure I'm making the point well, but I think "brightness" as described by the makers is not what humans actually see. I have x150% bulbs and they are only a tad brighter. But then I do have 4x H7 bulbs in my humble Skoda - I can't believe these were not standard in GTI's !.....