I'm aware that HN is mostly US focused. But I'm one of those iPhone users that doesn't have any relationship with ATT and I can emphatically say that this phone

I'm aware that HN is mostly US focused. But I'm one of those iPhone users that doesn't have any relationship with ATT and I can emphatically say that this phone is not the problem. I'm assuming I have the same baseband and radio as the US version, but dropped calls isn't a problem. And I've had tethering from the day I bought it (no hacks).