I've had two past experiences with Radioshack and both were excellent. When I preordered my white 16gb 4s with BestBuy, they decided to tell me on launch day that my phone was not coming in for another month (after telling me to come pick up the phone at the store), even though I was the first person to preorder the phone at the store. My friend told me that Radioshack had some so I stopped over and walked in and out with a 16gb white 4s.
Fastforward to the 5s. I made a reservation for a space grey 16gb 5s with them and was told that they most likely wouldn't have any ATT phones on opening day, but if something were to change they would give me a call. The day before launch day I got a call from them saying my phone was ready for pickup for the 20th. I asked if it would be really be there, and the guy told me it was in front of him with a post-it with my name on it.