I purchased this slim carbon fiber snap case for the 5s at the Apple store and so far I really like it. It is supposedly made from DuPont Kevlar fibers and is stronger than steel for the same thickness. I would agree that it is well made and strong. This case feels like it would be hard to break and it has a nice soft touch coating. It's a great minimal case for those of you that don't like cases or those that just want a very thin case. It goes on easy, but it is hard to remove. It's very durable though. It covers the back and sides, the top and bottom are exposed. I also got the two piece one, (rubber / carbon fiber mix). See them here...
http://www.evutec.com/products/AP-005-CS-KA1.html#page=tab1
http://www.evutec.com/apple.html
http://www.evutec.com/products/AP-005-CS-KA1.html#page=tab1
http://www.evutec.com/apple.html