My 3GS was bought new in 2009. It was replaced in an Apple store a little before the warranty ran out for a refurb after the mute switch gave out. It's all original.
Call bull all you like, it doesn't particularly scream "more quality!" to me. It looks just like every other phone.
The buttons are hardly chrome paint on plastic. And well, sure, you can compare the supposedly superior Galaxy S II to an older previous generation phone that you had a single bad experience with.
Oh, and I do apologise, the Galaxy S II does have glass on it's screen. Shame it's only a WXGA resolution, and is inset in all that plastic. But I'm sure that's still 'comparable' build quality to an iPhone 4 somehow.