Summary: I'm waiting for my third AD12-U. Originally purchased Feb. 27, 2013. First unit started to randomly shut down after one month. No temp issues, etc. RMA April 6, received second unit three weeks+, died completely mid-June. Had some hassles with mfg. website registering second box but generally they respond well. They received the second RMA delivery on July 3rd but I have not heard from them since second RMA approval notification. I'm waiting semi-patiently.