Well, from other threads, some people think that the speakers/microphones might stand out that much because stickers or some covers have been left in, so I'm worried this might later accumulate a lot of dust or block the speakers. I'm just hoping it's a cosmetic problem, rather than a hardware one ?.Those areas look different because they're the only holes that actually go all the way through (for the speakers and mics as you correctly say). Don't understand what exactly you think might affect the speaker or mic performance going forward?
I'm not so sure. Admittedly I've only seen one 16", my own but it doesn't have this at all. The speaker grills look perfect, no dark patches or anything. They also sound great.
So I don't think ALL of the 16s have this.