The problem here is not related to the "death-grip." The problems with AT&T's network affect all versions of the iPhone, not just the iPhone 4.
As a Canadian, I never get to see how well the AT&T data speeds are on an iPhone (the prices are insane for roaming), but on the times where I've needed to do voice calls, the AT&T experience is—at best—not great. I don't have that problem here in Canada.
As a Canadian, I never get to see how well the AT&T data speeds are on an iPhone (the prices are insane for roaming), but on the times where I've needed to do voice calls, the AT&T experience is—at best—not great. I don't have that problem here in Canada.