I had the zagg skin, then the bse skin came out, and was cheap, so I got 2.
The bse skin has higher quality production (they remove the negative skin, makes it easier to peel off the card), smoother application (the bse skin tends to float into place until you squeegee the water out. The zagg skin slides a bit and sticks), and better coverage (the zagg skin was in more pieces, and left the edge of the corners slightly exposed. the bse skin fit perfect, in fewer pieces, with a little bit more coverage).
Maybe due to the temperamentalness of applying the zagg skin, but the bse skin looks nicer, no bubbles.
looking back, I shoulda took pictures of the zagg skin on, but trust me, the bse skin is better.