I'm currently using sylvania ultrastar zxe's. very nice color temp with equal brightness to stock bulbs. probably the best you can get without upgrading to full blown hid kit in my opinion. don't pay over 40bucks for the set..
I am using the Eiko bulbs listed in my signature. I read a great review of them at Club Lexus and decided to take a chance. They are brighter and whiter than the stock bulbs, I can see farther down the road, but not as much as I would like. The central area closer to the car is much brighter. If they last as long as they claim, which is as long as stock, I will be happy. Got them at headlights123 dot com