I own a 2007 Chevy Cobalt LS and i was looking to upgrade my existing stock headlight bulbs. I know that PIAA is the better brand out there. Two different kinds fit my car and i was wondering which would give me a better, brighter, safer, more visible driving experience. Super Plasma GT-X Bulbs - PIAA GT-X replacement bulbs are designed with an exclusive purple low beam and an Xtreme White high beam. A purple topcoat gives the headlamp a bluish-purple look even when the lamp is turned off. GT-X bulbs feature PIAA's Xtra high efficiency technology that produces greater light output than the bulb's rated power consumption (for example, a bulb that consumes 45/65W of electricity has a light output that is similar to most 95/120W bulbs). GT-X bulbs are street-legal in Canada and all 50 U.S. states. PIAA 9007 Xtreme White Plus Pr - PIAA Xtreme White Plus halogen and driving light bulbs project a brilliant cool white light that comes very close to the color of expensive High Intensity Discharge (HID) lighting systems. Many Xtreme White Plus headlight bulbs feature PIAA Xtra high efficiency design that produces greater light output than their rated power consumption (for example, a bulb that consumes 45/65W of electricity has a light output that is similar to most 95/120W bulbs). www.PIAA.com