I use the monolith for my 17", the laptop sits deep enough where the zipper doesn't really touch it. If it does on the side, I haven't seen any visable scratches as of yet.
My only concern is that there is no padding what so ever on the top of the laptop (because the zipper is there). So, should it fall and somehow flip over 180, it'd be toast. I plan on modifying the case to include a nylon wrapped foam flat on the top, which will fold down when zipped shut. Other than that, it's great, it fit my jansport backpack perfectly and looks very unassuming when i'm on the train.