Just got a response from mas today.
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First off, I apologize that we didn't get things perfect the first time. There is absolutely no excuses for ruining the first impression. And yes, for such an expensive back, the fit SHOULD be perfect.
It has just been brought to our attention that the CDMA backs do not fit all 4S model the same way, as originally indicated by our supplier. We double check the backs and it seems that some do fit all the way, while others do not, so we will hold all orders until only the original parts come in. This is due to the slight changes made to the 4S housing frame, which is very similar to the CDMA version, but not 100% the same.
The good news is that the iPhone 4S parts are available, and we are getting them in this week. So I will need your help in sending the item back in, and we will replace the lens cover with the original 4S cover as well as the frame for you.
We will also refund you the postage fee for sending the item back in. Please print out this email, and insert it along with the return shipment.
Return address:
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I have to say that the response and ownership from them is sensational. Got the case I ordered delivered within a week (international), and the response to my problem within a day.
They accept full accountability and don't hide behind BS excuses. This is awesome customer service. I look forward to getting my replacement TI back now!