I got my iPhone 4 on launch day and had the same one until about a month after the 4S came out. Then, I got my 4S and it's the same one I'm using today, and barring any accidents will likely be the one I hand off to my significant other when I have the 5 in my hands.
By the way: I also had an iPad 2 from launch till a month after the iPad 3 came out, and I never returned or exchanged either the 2 or the 3. And I'm about as OCD as they come. Although I found no manufacturer defects, I know, obsess over and memorize every minute nick, scratch and scuff that ever appears on my MacBook, iPhone, iPad, and my car from daily use or accidents. I take fanatical care of my devices and no one else who's looked them over notice any flaws unless they look closely and I point them out, but I see and know them all very well.
But make no mistake, you're gonna get lots of threads from people who will be returning and exchanging iPhone 5 units 4, 5, 6, 7+ times because they perceive that the color is off, or they don't like the fit and finish, or they have light leaks. I still haven't decided if they're just incredibly unlucky, or if they're imagining problems that might not be there.
It happens every year. But people conveniently forget, and those "Tim Cook's lackluster keynote means Apple is going downhill" threads will abruptly give way to "the lack of quality control in the iPhone 5 means Apple is going downhill" threads. Mark my words.
I'll also just put this out there: If you swap out your iPhone 5 four or more times, and still aren't happy, it's probably time to just collect a refund and give up. Maybe postpone your purchase a month or two, or try a different store or method of purchase. Because if you can't get the "perfect" phone after try #4, it's highly unlikely that try #26 in the same time span will be any better.
“Insanity is doing the same thing, over and over again, but expecting different results.”
-Albert Einstein
