The recent issue tests after market bulbs, including the GE NightHawk and the Sylvania bulbs. Their results were inconsistent depending upon the car lamp in question. I found that the NightHawk did give me a boost in my 04 Town and Country and the GE/Toshiba inferred bulbs improved my 98 RAV4 much more than my PT Cruiser. Perhaps there is something about improvements being lamp specific. Richard.