On the positive side it's very very grippy. Much more grippy than the official Samsung case.
As others said, the stand seems fragile but it hasn't broken yet. The problem with the stand is that it is a little short so the phone leans back too far, about 45 degrees. I usually prefer the phone to be more upright on a stand, so for that purpose I prefer the folding leather type of case with built-in stand that allows a varying angle.
I don't mind the "S" design, but I think it's unnecessary, and it seems like the join between the clear part and black part of the case will be a weak spot over time.
Finally it's quite difficult to get on and off. That's an advantage if you just want it to stay on. It's a disadvantage if you want to take the phone out regularly e.g. to put in a sat-nav holder.
After using it for a few weeks I bought the official Samsung case, without the built-in stand. I prefer it, although it's less grippy and doesn't have the stand. It's better engineered than this one. I might even switch back to the folding leather case, although that makes the phone more bulky and difficult to put in a pocket.