My first one had a defective mic. This was evident when using Voice Recorder to leave memos, feedback from people on the other end of the call, and leaving test messages on my home voice mail. Other than that, the first phone worked flawlessly. GPS was fast and spot on. It was obvious that the fist phone had a defective mic when I swapped it out for the second one. My voice had a fuller sound, and was much clearer. But the GPS was buggy as hell, slow and the compass worked sporadically. I'm still evaluating the third one, which I got last night, and haven't had time to test the GPS yet. One thing that seems buggy on it though, is the inconsistent response from the bottom buttons. They all have the same responsiveness, except the menu button on the left, which needs to be hit over and over again to work. What's obvious though, is that Samsung's Quality control is less than ideal. It also sheds light on why some were happy with their GPS, while others claimed it just didn't work. So if you're happy with the phone overall, but you're experiencing problems with the GPS or lousy responsiveness from the bottom buttons, you may want to swap it out for another one. Not sure how many times I want keep doing this though, the third strike rule may stand.