Let me write my experience.
My first iPhone 3G unit had tiny hairline cracks on an edge of the white case. They exchanged it, but that one had a dust inside of the glass and a dead pixel.
I went back to the Apple Store with another appointment with iPod Bar specialist (They are not Geniuses but Specialists LOL). We tried 3 more units but they all had dust(s) and/or dead pixel(s).
The store was out of replacement phones, but the specialist made a service order and gave me a call when the replacement unit arrived. It took only a day.
Finally I'm with a perfect unit. No dust, no dead pixel, no crack, no nothing.
Usually this kind of devices get dust under the glass over time, but my iPhone (1st gen) has none after a full year of use in my pocket without case. That's probably because the original iPhone had completely sealed LCD/touch panel Unit with external glass. While it made out of warranty repair expensive, it did great job keeping dusts out.
Since the iPhone 3G has LCD/touch panel unit separable, I'm not sure how it will hold up over time. In other words, I'm not sure if swapping several times to get a perfect unit is worth the effort.
Some facts that I learned from my visits to Apple Store:
• Apple keeps "zero dead pixel" policy for iPhone 3G, unlike regular LCD equipped device like MacBook and iMac.
• They do accept exchange for dusts under the glass.
• They gladly accept multiple exchange to make sure you are happy with your iPhone (at least SF Chestnut St store did).
• The specialist I talked to was aware that the dust problem is "now or never" at least for 1st gen iPhone, and understood why I was being very picky about it.
This is just a guess:
• When you see dust(s) / dead pixel(s) in a replacement unit they have in stock, there is a chance that other replacement phones have same issue. This was true with my original and 3G iphone experience. Maybe some shipments are from lower QCed facility?? Don't freak out, take your time and wait for new shipment or try other store.
In the perfect world, there should be no dusts or dead pixels on "The Phone", but heck, it's a consumer device. And the 3G model is much cheaper, more consumer oriented product than the original iPhone.
I must say I am pleased and happy with Apple's generous exchange policy. If you bring your regular cell phone to other stores and try to exchange several times for tiny dust or dead pixel, store stuff will think you are crazy. 😝
Message was edited by: coelacanth