I returned x2 of these, one with a stuck pixel and dust, and another one with dust under the panel. I expect these will make their way to B-Grade as they will certainly still sell them, just not as brand new. B-Grade CAN be perfect... i.e it could just be a damaged box, but you can certainly get monitors with dead/stuck pixels etc.
what do you mean by dust? how do you identify that? also how much did it cost you to return the panels?