I still don't understand the dust under the screen. I keep mine in my pocket all the time, and my pockets are filled with all sorts of stuff (dust, lint, etc.).
If I were you I would keep it. You can try using blow off duster to blow some of that stuff away. It used to work for me with my other phones.
Struggled with the same question. Everything works fine on mine, except I have the dust issue. I debated whether or not it was a big enough deal to return and, based on horror stories here about the replacement being worse in other areas, I think I've decided to keep my first one and live with the dust since everything else works fine.
