Well, even though Ive never been through it so I dont really have a gague on pricing, Im willing to bet it's a lot like a paintjob.....you can get ones for under $1000 but the really reliable, high-quality ones are 3,4 and 5 grand. And just like the $1000 will fail/chip before the 3,000, my guess is that there are differences in glass and glues that would cause failure of a windshield sooner too. I can be completely wrong, this is just the only way I can imagine to explain such a price difference. Same goes for computer parts....cheaper will cost you more on the long run.