I had a NOKEY from InvisibleDefenders for several months & liked it. May end up getting another in the matte finish. I removed it because it totally clashed with my new cover - & had no issues with adhesive residue or impact on the key markings. The design I had was an allover abstract, so the keys were pretty well camouflaged, as the markings were in one of the colors of the design. (I liked that the keyboard was less obvious). If you use the keyboard a lot, though, it makes those keys a little harder to press (say, if you do word puzzles or make notes a lot). Didn't have that issue with the 5-way or page forward/back keys since their covers are cut out. So far I'm liking my Kindle naked under the cover.