Took my Iphone 3GS to them for battery issues. They were able to replace the battery in 24 hours.
The only issue we had was when we went to pick it up the next day they did not open on time. They are supposed to open at 10 and didn't open until 10:30. It's a little far from our house so we had to drive around for a while.
Service was good and everyone was very helpful and friendly.