Why would you want to stick with Halogen bulbs? Sylvania halogens, are just like Phillips, are just like PIAA, halogens bulbs are halogen Bulbs. They're all 12V @ 55W, the only way you're going to get a halogen bulb that is brighter and has more light output is by going to halogen bulb that operates at higher watts; 12V @ 80W or 100W (I know PIAA has some that go pretty high).
That being said I've had decent experience with halogen bulbs from Hoen:
http://www.hoen-usa.com/
When you start increasing the wattage on bulbs in electrical systems that aren't designed for it is when you can create problems... The factory wiring is gauged to run at 12V @ 55W, not 80W not 100W. The factory headlight housing is designed to handle heat from a 12V 55W Halogen bulb, not 80W or 100W. So when you increase just the wattage you're putting your factory headlight harness wiring at risk as well as your factory headlight housing. And for what you'll find is not a very noticeable amount of increased lumens over factory 12V 55W halogen bulbs.
The Tahoe's with non-HID headlights still have projectors for low beams don't they? So converting to HID on a halogen projector low beam will be much more "acceptable" than throwing an HID kit into a non-projector style halogen reflector headlight. If you're looking to increase the light output of your factory headlights find a quality HID kit and don't go over 6000K, personally I prefer the 4500-5500K max kelvin rating anything higher than that looks too aftermarket "ricer-ish" and actually decreases overall lumens (light output).
