Car guys - A longer lasting/cheaper alternative to SilverStars?

[TKHDebater]

The only thing not stock on my Honda Prelude are the headlight bulbs, not for looks but simply because I like the whiter light. The problem is that the SilverStars I've been putting in burn out too often, every four months it seems like, and at $20 a bulb that's a lot. Any other suggestions?