I just got it in the mail today. It included a screen protector, pieces for around the speakers, a back piece and side pieces. I ended up only putting on the screen and the back, because they add quite a bit of gloss and it really stands out against the exposed brushed aluminum. Since the pieces do not go edge to edge, they leave odd lines of bushed metal. Here is a picture of the bottom speaker (imgur: the simple image sharer). The front screen protector went on just like any other screen protector. The back piece was a bit of a challenge with the curve of the device. I found it best to line the piece up in the center and then brush out towards the edges. My back piece came with part of the adhesive exposed, so I have a few dust specks caught under and a couple air bubbles (which shouldn't be a problem since air bubbles will escape with in a couples days on their own). Here are some pictures of the back (imgur: the simple image sharer), (imgur: the simple image sharer).
Not sure how I feel about this yet. The protectors seem like they are very durable, they stick well and are a very good idea for protection without covering/hiding the device, but they don't cover the device well, at least the HTC One, and they give the phone a cheap plastic look and feel when the pieces are on the metal, which is a huge drawback with a high build quality device like the HTC One.