I have two iPhone 5's in my house, as well as two 4s's and a new iPad. Every device, including one of the iPhone 5's, has no wifi problems. My iPhone 5, however, suffers from slow and unreliable wifi. The problem is intermittent. It will be extremely fast one second, and the next, unbearably slow. I can take the other iPhone 5, or any other device and put it right next to my phone and run speedtests. My phone will go from 25-30 mbps, all the way down to 4 or 5 mbps, its all over the place. The other devices hold steady anywhere between 25-35 mbps. My problem is, what if I cannot replicate the problem at the genius bar tomorrow. How hard will it be to get a replacement if I can't replicate the problem?