Unless if a person knows what a One Plus One is no one would even know what you have in your hands. The minimalist design esthetic that makes this one a marvel to hold, and behold, is masked. But for the protection it is definitely a price to bear.
Somewhat squigy material (for a lack of a better term, rubberlike?) and the back is matte.
The sides are covered and raised by a fraction to provide added protection to the screen when put screen side down.
There are slots to access all ports bar the sim card. I only learned that after I put on the cover. It's not a major issue as that's not something you'll need access to every day