I received the case from China, and it seems good. Fits my tab 10.1 well, and it even has Samsung logo on 2 spots.
One thing that I'm disappointed about is that it seems like it's impossible to stand the tablet upward for watching movie or something? I don't know about official case by Samsung, but it doesn't stay upright. And there is no way for this to stay upright. I have no idea how the official one works. This one does have 2 rubber feet on one side too, but the other part that holds the tablet upright is slippery, so it falls.
I don't really care that much about that though as I don't want movie on it much, and it' hard to type while standing it upright, so I prefer it at the typing angle, which works very well.
Although the rating of the seller isn't the best, I received mine in about 2.5 weeks. I'd say it's pretty good, as it usually takes more for me when coming from China. And it was shipped out one day after I paid for the item. Of course, I don't know about your order..
Overall, I recommend this product and the seller.