I've been coming here for a few years now. Every time I visit, the staff is friendly, and the process is really organized, so I just keep coming back. I got a mini version, and it feels like it has better durability than ceramic (at least in my opinion). I've been using it without any issues so far. Oh, and thanks to Director Jeon Hye-yeon, I feel even more confident leaving it in their hands. She explains everything well and pays close attention, which I really appreciated. :)